New approaches to detection and identification of Rickettsia africae and Ehrlichia ruminantium in Amblyomma variegatum (Acari: Ixodidae) ticks from the Caribbean.

Imported from Africa in the 1700s and despite frequent modern eradication efforts, Amblyomma variegatum (F.) spread through the Caribbean by cattle transport, small ruminants, and migrating birds. A. variegatum is a vector for Rickettsia africae, the causative agent of African tick bite fever, and Ehrlichia ruminantium, the causative agent of heartwater. We examined 95 A. variegatum and six Rhipicephalus (Boophilus) microplus (Canestrini) collected from cattle at an abattoir in Antigua. Engorged tick extracts adsorbed on Nobotu filter paper strips and new nested polymerase chain reaction (PCR) assays for E. ruminantium and Dermatophilus congolensis were used to evaluate these ticks for the presence of these pathogenic bacteria. Amblyomma ticks (62.4%) contained R. africae DNA by PCR/restriction fragment length polymorphism analysis and DNA sequencing of the OmpA and 17-kDa antigen genes. Twenty Amblyomma and two Rh. microplus contained E. ruminantium DNA. No E. chaffeensis, Anaplasma phagocytophilum, Coxiella burnetii, or D. congolensis DNA was detected in these ticks. The continued presence of Am. variegatum in the Caribbean poses a significant risk of infection in cattle with E. ruminantium and in humans by R. africae. Eradication efforts are essential to prevent the further spread of Am. variegatum.

A review of hypogonadism and erectile dysfunction among HIV-infected men during the pre- and post-HAART eras: diagnosis, pathogenesis, and management.

Hypogonadism and erectile dysfunction (ED) appear to be more common among men infected with HIV compared to age-matched men within the general U.S. population. HIV providers should consider these conditions and utilize standardized evaluation and diagnostic criteria. Treatment of both hypogonadism and ED increases sexual function and quality of life; testosterone supplementation in the setting of hypogonadism may also improve lean body mass, mental status, and anemia. We review the epidemiology, diagnosis, pathogenesis, and treatment options of both hypogonadism and ED among HIV-infected men.

History of U.S. military contributions to the study of bacterial zoonoses.

Bacterial zoonoses have afflicted campaigns throughout military history, at times playing an important role in determining their outcomes. In addition, zoonotic bacteria are among the leading biological warfare threats. The U.S. military medical services have been at the forefront of research to define the basic microbiology, ecology, epidemiology, and clinical aspects of these diseases. This historical review discusses the military significance of plague, Q fever, anthrax, leptospirosis, bartonellosis, tularemia, and brucellosis and the U.S. military medical research counteroffensive. These contributions have ranged from basic molecular biology to elegant epidemiological surveys, from defining pathogenesis to developing new vaccine candidates. In an era of emerging diseases and biological weapons, the U.S. military will continue to lead a dynamic research effort to counter these disease threats.

Halting a pneumococcal pneumonia outbreak among United States Marine Corps trainees.

BACKGROUND: Streptococcus pneumoniae is the leading cause of bacterial pneumonia in all age groups. Identifying outbreaks of pneumococcal disease and key risk factors may lead to improvements in vaccination and prevention strategies for high-risk groups. A significant outbreak of S. pneumoniae pneumonia that occurred among Marine recruits is reported here. METHODS: An outbreak was investigated using standard microbiologic procedures and epidemiologic evaluation to define the extent of the outbreak, determine the microbiologic causative agent(s), identify risk factors for the development of disease, and institute preventive measures against further cases of pneumonia among recruits. RESULTS: Fifty-two cases of radiographically confirmed pneumonia occurred among 3367 Marine recruits over a 2-week period in November 2000. Twenty-five of these cases occurred in a single company of 481 men, with an attack rate of 5.2%. Twelve of the 25 cases were caused by S. pneumoniae, serotypes 4 and 9v. The outbreak rapidly ended following isolation of cases, prophylaxis with oral azithromycin, and administration of the 23-valent pneumococcal vaccine. CONCLUSIONS: This outbreak of pneumococcal disease occurred in the setting of intense military training and a crowded environment. The use of the pneumococcal vaccine year-round in military trainees and other high-risk populations to reduce pneumococcal disease should be considered.

Endemic infectious diseases of Afghanistan.

The current crisis in Afghanistan has resulted in an influx of Western military personnel, peacekeepers, humanitarian workers, and journalists. At the same time, unprecedented numbers of internally displaced persons and refugees have overwhelmed much of the already fragile infrastructure, setting the stage for outbreaks of infectious diseases among both foreigners and local populations. This review surveys the literature concerning the infectious diseases of Afghanistan and south-central Asia, with particular emphasis on diseases not typically seen in the Western world.