August 2006 Maine Epi-Gram

There are two major categories of Vibrio species: V. cholerae isolates that produce cholera toxin (referred to as toxigenic Vibrio cholerae and very rare in the United States), and all other Vibrio isolates such as V. haemolyticus, V. algonilyticus and those V. cholerae isolates that do not produce cholera toxin.

Since 1988, the federal CDC has maintained a database of reported infection with any species of Vibrio from humans in order to obtain reliable information on illnesses associated with the range of Vibrio species. This reporting system was initiated by the Food and Drug Administration (FDA), the federal CDC and the Gulf Coast states, but has since been adopted by many other states, including Maine. Participating states collect clinical data, identify history of seafood consumption and exposure to seawater in the seven days before illness, and conduct tracebacks of implicated oysters. In Maine, the Infectious Disease Epidemiology Program of the Maine CDC works in collaboration with the Department of Marine Resources and State Health and Environmental Testing Laboratory (HETL) to conduct relevant investigations of all reported cases of Vibrio.

This article summarizes data from the 2004 national Vibrio surveillance with highlights of confirmed cases reported in Maine from 2004 to 2005. Results are presented in two categories: toxigenic Vibrio cholerae, and all other Vibrio isolates.

No cases of toxigenic V. cholerae were reported in Maine in 2004. Nationally, a total of eight patients were identified. Four patients acquired the infection while traveling in Asia, and one from travel to Hawaii. Two patients were Georgia residents: one consumed oysters, later traced back to Florida, three days before onset of his symptoms and the other Georgia resident reported no known exposure to seafood in the 10 days preceding illness. The last of the eight patients was an Alabama resident who consumed oysters 10 days before onset of his symptoms. The oysters could not be traced back to their harvest site. Overall, three patients were hospitalized and one died.

Maine

In 2004, four Vibrio cases were reported to the Maine CDC. V. parahaemolyticus, the primary species seen in Maine, was isolated from three cases while V. alginolyticus was isolated from one case. Of the three parahaemolyticus cases, one was a fisherman with no known history of eating raw seafood in the seven days prior to illness but reported eating cooked clams and was routinely exposed to drippings from raw seafood; the second case was immune compromised with no travel history and no known seafood exposures; the parahaemolyticus case became sick after consuming raw oysters. The single case of alginolyticus was a fisherman who had a pre-existing wound with repeated exposure to seawater and contact with raw seafood.

In 2005, the Maine CDC received reports of two Vibrio cases. The first case was infected with V. parahaemolyticus and reported consumption of cooked shrimp, crab, and haddock. The individual also reported contact with a household member who had diarrheal symptoms during the exposure period. The second case, a victim of V. alginolyticus, reported travel to the British Virgin Islands in the seven days prior to illness and sustained a wound while swimming in the ocean waters around the islands.

Overall, six Vibrio cases were reported to the Maine CDC during the period from 2004 to 2005. None of the cases were hospitalized. There were no known deaths associated with Vibrio infection. Four isolates were classified as V. parahaemolyticus and came from stool samples, while two isolates were classified as V. alginolyticus and came from wound sites. Five of the six cases occurred in the summer months, consistent with the annual seasonal peak nationwide.

United States

On the national level, 479(1) cases (contributing 501 isolates) were reported to the Cholera and Other Vibrio Illness Surveillance System in 2004. Among patients for whom information was available, 173 (38%) of 460 were hospitalized and 39 (9%) of 443 died. V. parahaemolyticus was isolated from 240 (51%) patients, and was the most frequently reported Vibrio species. V. vulnificus, the most virulent strain, was isolated from 92 (19%) patients; 88% were hospitalized and 39% died. The number of patients from whom Vibrio species was isolated had a seasonal peak during the summer months of July and August. Consistent with previous years, the major sources of exposure included consumption of cooked and raw seafood, wound-exposure, handling seafood, contact with marine wildlife, and travel to a foreign country during the 7 days prior to the onset of illness.

Among the Vibrio isolates from all states, more than half were from stool, and the others from blood, wounds, ear, gallbladder, urine, and other sites. V. parahaemolyticus was the species most frequently isolated from stool. V. vulnificus was the species most frequently isolated from blood and from wounds.

The information gathered from Vibrio surveillance and presented in this article can be used to educate the public about the health risks associated with eating contaminated, raw or improperly cooked seafood, contact with marine wildlife, and exposures to contaminated seawater. In Maine, surveillance data is also used to assist the Department of Marine Resources in their efforts to promote the safety of shellfish by reducing contamination and illegal harvesting of commercial shellfish.

(1)In 2004, only toxigenic V. cholerae O1 and O139 were nationally notifiable, thus the true number of Vibrio isolates could be greater than reported. In April 2006, the federal CDC formally asked states to report all Vibrio species to the national database.

Background

The Infectious Disease Epidemiology program and the Maine Health and Environmental Testing laboratory of the Maine Center for Disease Control and Prevention monitor the incidence of animal rabies through mandatory reporting of suspected animal rabies by veterinarians, animal control officers, health care providers and other health professionals. This report summarizes surveillance data on animal rabies and rabies post-exposure prophylaxis (PEP) from 2005.

Methods

Rabies is diagnosed in animals by direct fluorescent antibody testing, preferably performed on central nervous system tissue. Maine’s Health and Environmental Testing Laboratory performs rabies testing on animals with human or domestic animal exposure, or animals without exposure at the submitters cost. During 2005, laboratory personnel followed up all rabies-positive animals identified to provide recommendations to prevent spread of the virus. In addition, standardized case report forms were completed for reported human or domestic animal exposures with potentially-rabid animals in 2005, which gathered information on the index-animal’s species, vaccination history and current health status, circumstances of the potential exposure, and public health actions taken to prevent spread of rabies such as PEP .

Results

A total of 683 animals were submitted for rabies testing during 2005. Of these, 61 (8.9%) were positive for the rabies virus, including 3 bats (big brown), 37 raccoons, and 21 skunks (Table).

The number of animal rabies cases identified during 2005 was slightly lower than the median number of cases reported during the previous 5 years (median 82, range 67-139). No domestic animals were identified as rabies-positive during 2005, whereas at least one domestic rabid animal was identified during three of the previous 5-years.

Table: Animals Submitted for Rabies Testing by Positive Result and Species
– Maine, 2005

Species	Received	Positive
no	No.	No.	%
Alpaca	2	0	0
Bat	196	3	1.5
Beaver	2	0	0
Bobcat	2	0	0
Cat	176	0	0
Cattle	8	0	0
Chipmunk	2	0	0
Coyote	3	0	0
Deer	1	0	0
Dog	69	0	0
Donkey	2	0	0
Ferret	2	0	0
Fisher	1	0	0
Fox	11	0	0
Goat	2	0	0
Groundhog	19	0	0
Horse	2	0	0
Mink	2	0	0
Mouse	1	0	0
Muskrat	3	0	0
Porcupine	1	0	0
Rabbit	3	0	0
Raccoon	118	37	31.4
Rat	1	0	0
Sheep	1	0	0
Skunk	43	21	48.8
Squirrel	6	0	0
Weasel	2	0	0
Wolf/Hybrid	3	0	0
Total	683	61	8.9

Animal Rabies by County - Maine 2005

image: count of rabid animals identified

Rabies Post Exposure Prophylaxis

During 2005, the Infectious Disease Epidemiology program received a total of 54 consultations regarding rabies post-exposure prophylaxis. Of these, 12 (22%) potential exposures warranting PEP were ruled out by a negative laboratory test. An additional 12 (22%) consultations involved domestic cats, dogs and ferret bites where a 10-day quarantine was recommended to determine if PEP was indicated. The majority (n=25, 46%) of consultations involved a potential exposure where no animal was available for testing or observation. Five (9%) consultations involved animals confirmed as rabies-positive.

Of the 54 consultations, 26 (50%) case-patients were recommended to receive rabies PEP. The majority of PEP patients were female (54%), and the age distribution ranged from 5 months to 61 years of age with a median age of 25 years. Exposure incidents associated with PEP included contact with bats (65%), raccoons (27%), dogs (4%), minks (4%), skunks (4%), and wolf-hybrids (4%).

Discussion

Animal rabies is found regularly among wild animals and occasionally among unvaccinated domestic animals in Maine. Recognition, prompt assessment, and management of potential rabies exposures will prevent human and domestic animal rabies in Maine.

The majority of patients receiving rabies PEP in 2005 may have avoided this invasive and expensive procedure had the animal suspected of rabies been captured and submitted for rabies testing. Informing members of the public about the risks of rabies when coming into contact with wild or unattended domestic animals may prevent future exposures. Municipal animal control officers, veterinarians, and health care providers greatly facilitate public education around rabies when assessing potential rabies exposures. Maintaining domestic animal vaccination status and avoiding animals that are unknown are effective methods of rabies prevention.

Suspect animal and human rabies is reportable immediately by telephone to our 24-hour disease reporting line 1-800-821-5821. Rabies PEP will be added as a reported condition when the notifiable disease rules change; until then, we request that public health partners reports of rabies PEP by calling the disease reporting line, or faxing reports to 287-8186. Epidemiologists are available to assess animal exposures, facilitate the testing of animals, and provide guidance on administering PEP.

For more information on animal rabies, see the Maine CDC rabies surveillance website (www.maine.gov/dhhs/boh/ddc/rabies_surveillance.htm) and the Maine Rabies Management Guidelines (2005) posted at (www.maine.gov/agriculture/ahi/Rabies%20Management%20Guide%202005.pdf).

Contributed by Anne Sites

Differences in PEP Based on Disease: Rabies vs. Hepatitis A vs. Pertussis

Surveillance Methods and Results

Human

Human surveillance relies on health care providers who consider arbovirus infection in their differential diagnosis and submit specimens to the Health and Environmental Testing Laboratory (HETL) for testing. In the course of the 2005 surveillance season, 72 patients were tested for arboviruses at HETL. Another individual, a Maine resident, was tested in Massachusetts. These individuals contributed a total of 97 specimens, consisting of 46 acute sera, 13 convalescent sera and 38 cerebral spinal fluids. Common symptoms exhibited by patients included fever (61%), encephalitis (17%), and aseptic meningitis (19%). None of the patients tested was positive for WNV. One patient tested false positive for SLE and two had indeterminate results for EEE; however, all were subsequently ruled out by confirmatory tests at the federal CDC’s vectorbone laboratory.

Avian surveillance is based on sightings of dead birds, primarily corvids (i.e. ravens, crows, and blue jays) , which are reported by the public via the Maine CDC’s Bird Reporting Hotline (1-888-697-5846). Dead birds determined to be viable are arranged for pick-up by a courier and tested for arboviruses by HETL. Statewide, 303 dead birds were reported. Of these, 70% (211/303) were corvids reported from all 16 counties. Thirty-three percent (69/211) of corvids were tested versus 16% (15/92) of non-corvids. Overall, nine corvids tested positive for arboviruses: eight tested positive for WNV and one tested positive for EEE. Only one of the positive birds was from outside of York County. All nine positive birds were collected in the months of August (five) and September (four). No non-corvid species tested positive for arbovirus.

Mosquito

There are approximately 42 different species of mosquitoes in Maine. Some of them have ranges that overlap, and others have separate ranges based on their specific breeding requirements. Mosquitoes that feed only on birds are maintenance vectors, and help maintain arboviruses in nature. Bridge vectors, mosquitoes that feed on both birds and mammals, are of most concern. This type of mosquito may become infected with an arbovirus by feeding on an infected bird, and then later feed on a human, thus providing the “bridge” that allows arboviruses to spread to humans. Forty-six mosquito pools from Cumberland County and 90 pools from York County were selectively tested for WNV and EEE; mosquito species tested included both maintenance and bridge vectors. One Culiseta melanura pool (a maintenance vector) from York County tested positive for EEE in October 2005. There were no other mosquito pools that tested positive for WNV or EEE in 2005.

Non-Human Mammals

Equines can be important indicators of epizootic activity and human risk for both WNV and EEE. They may be particularly useful sentinels in rural areas, where dead birds may be less likely to be detected. In 2002, for example, equine WNV cases were the first indication of WNV activity in 16% (95/589) of the counties where human disease was reported in the United States. The non-human mammal component of Maine’s arboviral surveillance program consists of testing any equine, llama, or alpaca that has died with neurological symptoms for WNV and EEE. All non-human mammal specimens submitted for arboviral testing are first tested for rabies. There were four non-human mammals tested for arboviruses in 2005: two horses, both from York County, tested positive for EEE in September 2005, and two llamas, also from York County, were negative for any arborviruses.

Recommendations

Although Maine did not report any human case of arboviral infection in 2005, WNV and EEE have already been detected in mosquitoes, birds, and horses while Powassan virus has been identified in humans in Maine. It is assumed, therefore, that residents or visitors to the State who are exposed to the outdoors are at risk of arboviral infection, especially during the spring, summer, and fall seasons, when temperatures are ideal for mosquitoes and ticks. For this reason, healthcare providers are advised to maintain a high index of suspicion for arbovirus infections as the warm season begins.

EEE, WNV and other arboviral infections should be seriously considered in any individual, but especially those over age 50 or younger than age 15 years, who has onset of otherwise unexplained encephalitis, meningitis, myelitis or fever in the late summer or early fall. The local presence of arboviral enzootic activity should further raise the index of suspicion. Diagnostic testing of serum and cerebrospinal fluid for arboviral infection is available at no cost through the Health and Environmental Testing Laboratory. Maine CDC requests that all specimens for arboviral testing be submitted to the State lab in Augusta rather than commercial laboratories to ensure a quicker turnaround time and immediate access to test results for surveillance and response purposes. For information on collecting and submitting specimens for testing call 1-800-821-5821.

Avian Surveillance

Avian surveillance will tentatively begin in mid-June and end in mid-October. To report a dead bird, please contact the toll-free Bird Reporting Hotline at 1-888-697-5846. Testing of dead birds in 2006 will be limited to corvids, unless there are unusual circumstances. Captive pheasants and emus are notable exceptions because they are known to be highly susceptible to EEE infection, and owners of these species or veterinarians providing care for these species are also encouraged to call the Bird Reporting Hotline if they detect severe illness or death in their birds. Even though not all dead birds will be collected or tested, all reports will be recorded; this information can be very useful in detecting clusters of dead birds that occur over time, and can indicate if and when the testing protocol should be modified.

Non-Human Mammal Surveillance

Equines, llamas, and alpacas make up an important component of the Maine CDC Arboviral Surveillance program. Owners and veterinarians are urged to report cases of illness in these species so that the Maine CDC can determine if arboviral testing is appropriate. Any equine, llama, or alpaca that dies with neurological abnormalities, or is euthanized due to illness with neurological abnormalities, should be reported to either the Maine CDC Disease Reporting Hotline at 1-800-821-5821 or the Bird Reporting Hotline at 1-888-697-5846.

Only dead animals of these species can be tested for arboviral infection, as the Maine CDC must first test them for rabies. If a veterinarian, while treating an animal of these species, obtains serology results positive for an arbovirus, the Maine CDC urges them to report those results to the phone number stated above, even if the animal survives. It is also important that a WNV/EEE vaccination history be submitted with any specimens and included in any reports. Reports of potential non-human mammal arboviral cases can be made year-round.

Mosquito surveillance will also tentatively begin in mid-June and end in mid-October. In 2006, mosquito surveillance will have a greater emphasis than avian surveillance, as it will provide a more reliable indication of at-risk areas, by identifying mosquito species, density, infection rates, and breeding areas. Mosquito surveillance will consist of collecting adult mosquitoes of both maintenance and bridge vector species, primarily from southwestern Maine and the Lewiston and Bangor areas, specifically in urban, high-population density, and other key geographic (i.e. red maple swamps, etc.) areas. Collected mosquitoes will be speciated, and selected pools will be tested for arboviruses.

To complement this effort, the Maine CDC encourages all municipalities, especially those in southern Maine, to cooperatively establish local mosquito surveillance and abatement programs. This will expand surveillance coverage as well as increase the timeliness and effectiveness of future control efforts.

Diagnosis and Management of Tickborne Rickettsial Diseases: Rocky Mountain Spotted Fever, Ehrlichioses, and Anaplasmosis-United States

In March of 2006, the Centers for Disease Control and Prevention, Viral and Rickettsial Zoonoses Branch, released a Morbidity and Mortality Weekly Report (MMWR) summarizing recommendations for the management of tickborne rickettsial diseases (TBRD). TBRD are clinically similar, etiologically distinct illnesses often presenting with nonspecific, “viral-like,” symptoms early in the infection. TBRD can result in severe morbidity and even death, in otherwise healthy individuals, if not treated as soon as possible with effective antimicrobial therapy. TBRD often present with nonspecific symptoms that may be difficult to distinguish from other infectious and noninfectious disease processes thereby delaying appropriate treatment.

TBRD include human granulocytotropic anaplasmosis (HGA, caused by Anaplasma phagocytophilum, and formerly known as human granulocytic ehrlichiosis), human monocytotropic ehrlichiosis (HME, caused by Ehrlichia chaffeenis), rocky mountain spotted fever (RMSF, caused by Rickettsia rickettsii), Ehrlichia ewingii infection as well as other more recently emerging TBRD.

The incidence of TBRD has risen over the past decade. The degree to which TBRD infections have risen depends on many factors: persistence of the pathogen in the environment, geographic distribution of the transmitting species of tick, life cycles and behaviors of the tick vectors and their reservoirs, behaviors that place humans at risk for tick exposure, attachment and infection and more frequent diagnosis and reporting.

Epidemiology

TBRD are reported each month of the year with the majority of cases reported from April to September. Travel related cases, infection acquired while traveling within the United States and outside the United States, are reported throughout the year as well. Males appear to be at higher risk for TBRD infection perhaps due to increased recreational and occupational exposures. The frequency of TBRD is highest in adults. For HGA, the incidence of reported illness is most common in 60-69 year olds. For HME, the incidence of reported illness is greatest in 70 year olds and for RMSF, most commonly reported in 40-64 year olds. Higher frequency of reports in adults may be related more to susceptibility to overt infection rather than higher infection rates. RMSF and HME are most commonly reported in the south central and southeastern United States. In New England, the most common TBRD is HGA. (Note: an upcoming issue of the Epi-Gram will include a summary of Maine rickettsial disease data.)

Clinical History, Signs and Symptoms

Most infected individuals present for medical care within the first week of symptom onset, before a TBRD rash develops and before antibody to the rickettsia, ehrlichia or anaplasma begins to rise, making confirmation of rickettsial infection difficult. Clinical history taking should include identifying recent tick bite or exposure to tick habitats (within 14 days), travel to TBRD endemic areas and identifying any similar symptoms in family, friends, co-workers or pets. Clusters of cases have been recognized in families, soldiers on maneuvers, golf partners and co-workers who share similar exposures to infected tick habitat.

Early clinical presentation of HGA, HME, RMSF and E. ewingii infection include fever, shaking chills, severe headache, myalgia and malaise. Adults may complain of photophobia. Nausea, vomiting and anorexia may also be reported early in the infection. In children, with HME or RMSF, abdominal pain, altered mental status and conjunctival injection are frequently noted symptoms. Severe abdominal pain and menigoencephalitis are infrequent signs of TBRD. A rash, after the fever, is usually observed in RMSF, occasionally observed in HME and rarely evident in HGA or E. ewingii infection. . Untreated or later stage TBRD and TBRD in patients with compromised immune systems may have severe manifestations such as renal failure, myocarditis, acute respiratory distress syndrome, hypotension and toxic shock syndrome, meningoencephalitis, multiple organ failure and tissue necrosis.

Other clinical suggestions of TBRD, include abnormalities in complete blood count, metabolic panel, CSF analysis and peripheral blood smear:

Laboratory Confirmation

Suspicion of TBRD based on epidemiological and clinical information should be confirmed with laboratory diagnostic tests. The most effective way to confirm TBRD is with indirect immunoflourescent antibody assay, in paired serum samples, with the first serum specimen taken at least one week after onset of illness and the second specimen taken 2-3 weeks after the first. A fourfold rise in IgG or IgM, with clinical and epidemiological evidence of infection indicates a TBRD.

There are limitations to all other laboratory methods. Culture is difficult as rickettsia, ehrlichia and anaplasma are obligate intracellular pathogens making the process of culturing labor intensive. Ehrlichia chaffeensis and Anaplasma phagocytophilum produce morulae, microcolonies of pathogens that invade leukocytes. Morulae may be visualized in peripheral blood smears stained with eosin-azure dyes, such as Wright-Giemsa stain. The absence of morulae does not rule out TBRD as blood smears do not always reveal morulae and are not useful for the diagnosis of RMSF. Nucleic acid detection (PCR) and immunohistochemical (IHC) staining detection methods are not currently widely available or fully standardized. The sensitivity of these tests is dependent on the timing of sample collection, the distribution of pathogen in the sample and the specific type of rickettsial infection. Evolution of PCR testing and tests in combination may provide more thorough diagnostic information. At this time, paired serum sampling is still the gold standard for laboratory diagnosis.

Treatment and Management

Treatment is guided by clinical symptoms, history and physical and laboratory findings. If TBRD is strongly suspected, treatment should be initiated pending IFA, smear, PCR or culture results. Antibiotic coverage for TBRD, as well as other possible diagnoses (most notably meningococcal disease), should be considered to prevent severe outcomes.

Not all cases of TBRD will require hospitalization and supportive therapy. Some cases may be well-managed as outpatients with doxycycline as the antibiotic of choice for presumptive or confirmed TBRD in children and adults. Limited courses of doxycycline may be considered for children and pregnant women in situations of severe illness. Severe illness will most likely require inpatient supportive therapy.

Preventive antibiotic therapy is not recommended after a tick bite even in TBRD endemic areas. Not all ticks, even in endemic areas, are infected with rickettsia, ehrlichia or anaplasma, making the risk of infection relatively low.

Prevention

There is no licensed vaccine. Prevention is focused on avoiding tick attachment and removing ticks promptly.

Please note: clinical signs and symptoms presented are not pathognomonic for TBRD. Diagnosis of tickborne illness is complicated. Other bacterial and viral tickborne illnesses may present with similar symptoms: Lyme Disease, babesiosis, and powassan infection. Other infectious and non-infectious disease processes may also present similarly. For more detailed clinical management guidelines, including case studies, differential diagnoses table, treatment options, tick identification and geographic distribution of cases, please see the full report at: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5504a1.htm

For additional information regarding TBRD, clinical features, epidemiological information, public health control measures and prevention education please see:

or contact the Maine Center for Disease Control and Prevention at www.mainepublichealth.gov or 1-800-821-5821

Rabies is an infectious viral disease that affects the nervous system of humans other mammals. People get rabies from the bites of animals with rabies (rabid animals). Wild mammals, like a raccoon, skunk, fox, coyote, or bat, that bite or otherwise expose persons, pets or livestock should be considered potentially rabid.

Animal rabies is a relatively common occurrence in Maine, with 61 rabid animals reported in 2005 and 69 reported in 2004. Rabies is most often identified in raccoons and skunks, but is also identified in bats. Rabid animals were submitted to Maine’s Health and Environmental Testing Laboratory from all on Maine’s 16 counties.

Because rabies is a fatal disease, the goal is first to prevent human rabies exposure by education, pet vaccination, and stray control programs, and second, to prevent the disease by human treatment if exposure occurs. But what defines a rabies exposure? Many health care providers struggle with this question when people present to their office or emergency department concerned about rabies.

Rabies is transmitted to humans only by directly introducing the virus into bite wounds, open cuts in the skin, or onto mucous membranes from saliva or other potentially infectious material such as neural tissue. In defining an exposure consider the circumstances of the incident. Was the incident a bite, non-bit, or undetected bite exposure? These are defined below:

Rabies virus may be excreted in the saliva of infected dogs, cats and ferrets during illness and/or for only a few days prior to illness or death. Management of bite incidents of animals other than dogs, cats, and ferrets depends on the species, the circumstances of the bite, the epidemiology of rabies in the area, the biting animal’s history, current health status, and potential for exposure to rabies.

In each of these situations, consideration must first be given to obtaining and testing the animal in question, the bat, raccoon and stray dog. If the animals are not available for testing, each person should be consulted to determine if there is evidence of a bite or non-bite exposure. The local epidemiology of rabies can also be considered.

A1. Test the bat if available. If the bat tests positive for rabies or is unavailable for testing, initiate post exposure prophylaxis (PEP) for the six-month old girl.

A2. This is an example of a possible non-bite exposure. Test the raccoon for rabies. If the raccoon tests positive, the dog should be boostered and quarantined. PEP may be indicated for the businessman only if the he had direct contact with the raccoon’s brain or other neurological tissue and an open wound at the site of contact.

A3. In this circumstance, the country and city this incident took place is important when considering PEP. If the bite occurred in an area where rabies is common in dogs, which is likely in this case, immediate PEP is warranted.

The persistent incidence of animal rabies and the critical importance of preventing human rabies cases require that clinicians be diligent in assessing potential rabies exposures. Report suspected cases of animal rabies to Maine CDC by calling 1-800-821-5821. Epidemiologists are available 24 hours a day to guide clinicians and members of the public in evaluating potential rabies exposures.

The eleventh annual National HIV Testing Day is Tuesday, June 27th. This annual observance is critical to the fight against HIV/AIDS because it presents an opportunity for people throughout the state of Maine to learn their HIV status and gain the knowledge they need to take control of their health. It is estimated that approximately 400 people in Maine are HIV positive and do not know it. This represents 400 people who may unknowingly transmit HIV and who do not have access to much needed HIV medical services.

Last year, 58 people were newly diagnosed with HIV in Maine. Currently, gay, bisexual and other men who have sex with men represent over 60% of the new infections in the State of Maine. Other people at greatest risk for HIV infection include injection drug users and females who are knowingly or unknowingly partnered with an injection drug user or a man who has sex with other men.

The CDC initiative Advancing HIV Prevention: New Strategies for a Changing Epidemic calls for including HIV testing as a routine part of medical care to increase the number of HIV-infected persons who are aware of their positive serostatus. National HIV testing day is an excellent opportunity for healthcare providers to begin addressing HIV risk and testing as part of a patient’s on-going health care.

Data from the Maine Youth Risk Behavior Survey: Health Risks among Youth with Same-Sex Partners

Research has shown that youth who engage in same-sex sexual contact are disproportionately affected by certain health risks when compared to youth with opposite-sex contact. Such risks include violence and harassment, suicidal ideation and behavior, alcohol and other substance use, and unhealthy weight control practices. Many of these health risks have been documented through studies of recent Youth Risk Behavior Surveys (YRBS) conducted in Massachusetts and Vermont (Robin et al., 2002).

The Maine YRBS is administered every other spring to students at randomly selected high schools and middle schools to measure a variety of health risk behaviors. In 1995, the Maine YRBS began asking high school respondents (grades 9 to 12) the gender of their sexual partners. Since 1995, just under 8% of sexually active high school students reported same-sex sexual contact. This includes youth who had sexual contact with only same-sex partners (3.6%) and those who had contact with both same- and opposite-sex partners (4%).

Data from the 1995, 1997, 2001 and 2003 Maine YRBS were aggregated to compare responses from students with same-sex sexual partners to those who had only opposite-sex partners. Initial findings demonstrate that youth in Maine who have same-sex partners are disproportionately affected by certain health risks. These risks are grouped and summarized below:

In general, those students who reported contact with both same- and opposite-sex partners cited health risk behaviors in higher proportions than those with same-sex partners only. Reasons for this are not entirely clear. Differences between the two groups warrant more examination and study.

The inequalities in health status noted above are known as “health disparities” because same-sex contact does not, in itself, biologically determine or directly cause poor health status. Research has shown that sexual minority youth are remarkably healthy and exhibit impressive coping skills and resilience when faced with hostilities both at home and at school.

In Maine’s public health plan Healthy Maine 2010: Longer and Healthier Lives and Healthy Maine 2010: Opportunities for All, sexual minorities are identified as one of eight population groups affected by health disparities on which Maine CDC will focus its efforts. Health disparities among this population need to be further explored, with prevention interventions developed to target youth in both school and non-school settings.

Pertussis is an acute infectious disease caused by a gram-negative rod: Bordetella pertussis. Pertussis is transmitted from person to person through aerosolized droplets. The most susceptible are infants and the geriatric population.

CDC specifies that for a case to be defined as a pertussis case, the patient must present with cough illness lasting for at least two weeks with paroxysms of coughing, inspiratory “whoop” or post-tussive vomiting without other cause. The laboratory criteria for confirmation of pertussis is the culture of B. pertussis from a naso-pharyngeal (NP) swab specimen or alternatively, the identification of B. pertussis by PCR. Both tests are performed at Maine's Health and Environmental Testing Laboratory (HETL).

Isolation of B. Pertussis from a naso-pharyngeal swab remains the gold standard for laboratory diagnosis of pertussis. However, several providers have used serological tests after a sales pitch by representatives of commercial laboratories. Maine CDC encourages clinicians to continue to use culture or PCR for laboratory confirmation of pertussis to the exclusion of all other tests. Both tests are performed at the State of Maine Health and Environmental Lab (HETL) in Augusta.

Pertussis incidence has been decreasing since the introduction of the vaccine in the 1940s. Resurgence has been noted since the 1980s, with the number of cases in 2003 equaling those of 1964. Figure 1 presents the frequency of monthly reported cases in Maine between 2001 and 2005.

The crude incidence rate for Maine in 2005 is 5.54 per 100,000. Maine’s age-adjusted rate is 3.39 per 100,000 compared to a national average incidence rate of 3.3 per 100,000.

Information for Healthcare Providers on New Tdap Vaccine

In March, 2006, the Center for Disease Control and Prevention’s Advisory Committee on Immunization Practices (ACIP) provided provisional recommendations for the use of the newly available combined tetanus, diphtheria and pertussis (Tdap) vaccine for adults.

This Health Advisory provides a summary of important new recommendations. Healthcare providers are encouraged to take advantage of this information as soon as possible by reviewing their current Td vaccination practices and considering implementing policies to maximize administration of Tdap to all persons for whom the vaccine is indicated.

This information is especially relevant for practices where Td vaccine is provided to adults, including emergency departments and other settings where wound care is provided, clinicians caring for pregnant women, infants, and their families, and for health care facilities.

Pertussis is a highly contagious respiratory tract infection. Although most children are protected against pertussis by vaccination during childhood, immunity wanes over time and leaves adolescents and adults unprotected. In 2004, U.S. adults 19–64 years of age accounted for 7,008 of 25,827 (27%) reported pertussis cases. The true number of cases among adults 19-64 years of age is likely much higher, estimated at 600,000 annually. The clinical presentation of pertussis in adults ranges from mild cough illness to classic pertussis (i.e., prolonged cough characterized by paroxysms, post-tussive vomiting, and inspiratory whoop). Complications include rib fractures resulting from severe cough and pneumonia requiring hospitalization. Adults with pertussis can transmit the infection to other people, including infants. Infants are at highest risk of pertussis-related complications and death compared with older age groups.

Tdap for age 11-18 will be available through the VFC (Vaccines For Children) program beginning July 1, 2006. For those not eligible for VFC the provider will have to purchase their supply of the vaccine privately.

ACIP recommendations for Tdap (ADACEL TM and BOOSTRIX ®) among adolescents 11-18 years of age were published in the March 24,2006 MMWR: Preventing Tetanus, Diphtheria, and Pertussis Among Adolescents: Use of Tetanus Toxoid, Reduced Diphtheria Toxoid and Acellular Pertussis Vaccines . http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5503a1.htm

The following provisional recommendations for a single dose of Tdap (ADACEL TM) apply to adults 19-64 years of age who have not received Tdap previously.

All clinically significant adverse events following vaccination should be reported to VAERS, even if a causal relationship to vaccination is uncertain. VAERS reporting forms and information are available electronically at http://www.vaers.hhs.gov/ or by calling (800) 822-7967. Providers are encouraged to report electronically at https://secure.vaers.org/VaersDataEntryintro.htm.

Department of Health and Human Services
Maine Center for Disease Control and Prevention
(Formerly Bureau of Health)
286 Water Street
11 State House Station
Augusta, ME 04333-0011