Bonnie L. Smoak

Malaria among United States troops in Somalia

PURPOSE United States military personnel deployed to Somalia were at risk for malaria, including chloroquine-resistant Plasmodium falciparum malaria. This report details laboratory, clinical, preventive, and therapeutic aspects of malaria in this cohort. PATIENTS AND METHODS The study took place in US military field hospitals in Somalia, with US troops deployed to Somalia between December 1992 and May 1993. Centralized clinical care and country-wide disease surveillance facilitated standardized laboratory diagnosis, clinical records, epidemiologic studies, and assessment of chemoprophylactic efficacy. RESULTS Forty-eight cases of malaria occurred among US troops while in Somalia; 41 of these cases were P falciparum. Risk factors associated with malaria included: noncompliance with recommended chemoprophylaxis (odds ratio [OR] 2.4); failure to use bed nets (OR 2.6); and failure to keep sleeves rolled down (OR 2.2). Some patients developed malaria in spite of mefloquine (n = 8) or doxycycline (n = 5) levels of compatible with chemoprophylactic compliance. Five mefloquine failures had both serum levels > or = 650 ng/mL and metabolite:mefloquine ratios over 2, indicating chemoprophylactic failure. All cases were successfully treated, including 1 patient who developed cerebral malaria. CONCLUSIONS P falciparum malaria attack rates were substantial in the first several weeks of Operation Restore Hope. While most cases occurred because of noncompliance with personal protective measures or chemoprophylaxis, both mefloquine and doxycycline chemoprophylactic failures occurred. Military or civilian travelers to East Africa must be scrupulous in their attention to both chemoprophylaxis and personal protection measures.

The Effects of Inadvertent Exposure of Mefloquine Chemoprophylaxis on Pregnancy Outcomes and Infants of US Army Servicewomen

During US military operations in Somalia, mefloquine, a drug for malaria chemoprophylaxis, was not approved for use in pregnant women. Some female soldiers inadvertently used mefloquine before becoming aware of their pregnancy. A registry was established to follow the outcomes of these pregnancies. Questionnaires were administered at the time the pregnancy was diagnosed, after termination or delivery, and at 1 year after birth. Seventy-two soldiers were eligible for the registry. There were 17 elective abortions, 12 spontaneous abortions, 1 molar pregnancy, and 23 live births. The outcome for 19 soldiers was unknown. An unexpected high rate of spontaneous abortions was observed. All infants were healthy at birth, with no major congenital malformations. One infant died at 4 months of viral pneumonitis. At 1 year of age, 13 infants were reported to be healthy, with normal cognitive and motor development. This study provides additional postmarketing data that mefloquine does not cause gross congenital malformations.

Q Fever and the US Military

To the Editor: Q fever is a zoonotic disease caused by the rickettsialike organism Coxiella burnetii. The disease has a worldwide distribution and can infect many different species, although cattle, sheep, and goats are the primary reservoirs (1). Transmission to humans usually occurs by inhaling dust or aerosols from infected animals, and approximately half of infected persons manifest clinical symptoms. In acute Q fever infection, the 3 main sets of symptoms are flulike syndrome, pneumonia, and hepatitis (2,3). Q fever has military relevance not only in its potential use as a bioterrorism agent, but also because of the risk for natural infection in deployed military personnel. Thousands of cases of Q fever have been seen in military personnel since the disease was first reported in the 1930s (4). Since the most common mode of transmission is airborne, personnel do not need to have direct contact with infected animals to be exposed. C. burnetii was first recognized as an infectious disease threat to US military troops serving in Iraq in 2003 during a pneumonia outbreak investigation. Nineteen cases of severe pneumonia, including 2 deaths, occurred from March 1 to August 20 (5). A case was defined as occurring in a patient with bilateral alveolar infiltrates that required intubation and mechanical ventilation. This investigation involved extensive serologic testing for possible infectious causes of pneumonia, including C. burnetii. Of 19 patients with severe pneumonia tested for C. burnetii, 3 had positive antibody titers by immunofluorescence assay (IFA). No other infectious cause was confirmed for the remaining cases of pneumonia. Although C. burnetii was not determined to be the cause of the pneumonia outbreak, the finding of 3 patients with positive antibody titers launched an effort to ascertain other cases of Q fever among military personnel who served in Iraq during that time. Approximately 62 cases of pneumonia, both severe and nonsevere, occurred in Iraq from March 1 to August 20, 2003. A pneumonia case was defined as occurring in a patient with a chest radiograph suggesting pneumonia and ≥1 of the following symptoms: fever, cough, or shortness of breath. The Defense Medical Surveillance System (DMSS) was queried to determine how many patients had both predeployment and postdeployment serum samples available for Q fever testing. The Army Medical Surveillance Activity, which operates DMSS, also maintains the Department of Defense Serum Repository and stores serum from service members after mandatory HIV testing and deployment processing (6). Predeployment sera must be collected within the year before deployment. Twenty-two soldiers had predeployment and postdeployment sera available; samples were tested for phase I and phase II antibody to Q fever by using IFA. Results showed 5 additional soldiers in whom pneumonia was diagnosed while serving in Iraq and who seroconverted to C. burnetii before postdeployment serum draws (Table). All predeployment antibody titers for both immunoglobulin (Ig) G and IgM were negative in these 5 soldiers, with an IFA titer of 1:16 as a cutoff. Table Postdeployment serum antibody titers to phase II antigen for Q fever in 8 US military personnel who served in Iraq, March 1–August 20, 2003* The initial 3 Q fever patients ascertained through the pneumonia outbreak investigation were extensively interviewed for possible exposures. All 3 patients first experienced symptoms while in northern Iraq and reported contact with domestic animals, including dogs, cats, sheep, goats, and camels. Two of the patients reported tick bites within 30 days before becoming ill, and 1 reported drinking raw sheeps milk. The 5 other patients who became ill with pneumonia also first sought care while in northern Iraq. Predeployment sera from these 3 patients were also tested for C. burnetii by IFA, and all samples were negative for both IgG and IgM. Extremely limited information is available on Q fever disease prevalence in Iraq, either in animals or humans. Iraq is primarily an agricultural country, and nomadic herding takes place countrywide, except in the northernmost regions and along the eastern border, where adequate land is available for grazing livestock. The most common livestock in Iraq are cattle, sheep, and goats (7). Although herds of infected animals may exist in any region of Iraq, larger concentrations of livestock may exist in northern areas, where land is suitable for ruminants to graze. This concentration could lead to a higher risk for transmission to humans because the chance of contact with infected animals would be greater. These data indicate the potential importance of C. burnetii as an infectious disease threat to US military troops in Iraq. Healthcare providers should include Q fever in their differential diagnosis of community-acquired pneumonia and consider adding doxycycline to a combined antimicrobial drug regimen to presumptively treat severe pneumonia. Future studies to be completed include case ascertainment to locate US troops who were infected with Q fever while in Iraq and in whom pneumonia or other clinical manifestations of illness may have developed. Research was conducted in compliance with the Animal Welfare Act and other federal statutes and regulations relating to animals and experiments involving animals and adheres to principles stated in the Guide for the Care and Use of Laboratory Animals, NRC Publication, 1996 edition.

Detection of PCR products of the ipaH gene from Shigella and enteroinvasive Escherichia coli by enzyme linked immunosorbent assay

PCR techniques applied to diarrheal stools reliably diagnose Shigella and enteroinvasive Escherichia coli (EIEC) infections. Identification of PCR products using agarose gel electrophoresis (AGE) and hybridization with DNA probes has several shortcomings. Automated methods of identifying PCR products that process larger numbers of specimens can facilitate epidemiologic studies and standardize results. In this study, we used ELISA following PCR to detect ipaH gene sequences of Shigella and EIEC from 89 diarrheal stools. Results of ELISA were compared with AGE with and without DNA probe, and with culture. Two specimen preparation methods were compared as well: boiling/centrifugation, and purification with silicon dioxide (SiO(2)). Both PCR product-detection methods identified significantly more infections than did culture. PCR-ELISA detected significantly more infections than PCR-AGE when processed using SiO2 (P = 0.014). PCR-ELISA allows screening of larger numbers of specimens, automates test results, and avoids use of mutagenic reagents. PCR-ELISA is faster than PCR-AGE when testing large numbers of specimens, although not when testing small numbers of specimens.

Helicobacter pylori Infection in Desert Storm Troops

To determine whether military personnel deployed outside the United States are at increased risk of Helicobacter pylori infection, we evaluated U.S. Army personnel who served in the Persian Gulf from August 1990 to April 1991. Of 204 subjects from whom paired predeployment and postdeployment serum specimens were obtained, 76 (37%) were seropositive for IgG antibody to H. pylori before deployment by an enzyme-linked immunosorbent assay. Of the 111 initially seronegative subjects evaluated before and after a 7.5-month deployment, five (4.5%) seroconverted. The calculated annual seroconversion rate was 7.3%. In a postdeployment questionnaire, 62% of soldiers reported an episode of diarrhea while deployed, but there was not an increased rate of diarrhea or upper gastrointestinal symptoms in soldiers who were infected before deployment or in those who seroconverted. These data suggest that the risk of H. pylori infection increases during long-term deployment and that acute infection is not distinguishable from other gastrointestinal illnesses encountered during deployment.

Dengue serotypes 2 and 3 in US forces In Somalia

Abstract : A prospective investigation of febrile illnesses among US forces in Somalia revealed dengue viruses as an important identifiable cause. 90 consecutively admitted patients temperatures of at least 38.1 deg C were studied. Flavivirus infection was confirmed by positive dengue IgM and/or hemagluttinin inhibition tests in 15 of 84 individuals tested. Dengue viruses were isolated from 14 cases with acute flavivirus infection; viral serotypes included dengue 2 (12 cases), dengue 3 (1 case), and mixed dengue 2/3 infection (1 case). Our report documents the detection of dengue 3 in north-east Africa. Dengue, Somalia, Flavivirus

Novel Bartonella Agent as Cause of Verruga Peruana

While studying chronic verruga peruana infections in Peru from 2003, we isolated a novel Bartonella agent, which we propose be named Candidatus Bartonella ancashi. This case reveals the inherent weakness of relying solely on clinical syndromes for diagnosis and underscores the need for a new diagnostic paradigm in developing settings.

Drug Susceptibility and Genetic Evaluation of Plasmodium falciparum Isolates Obtained in Four Distinct Geographical Regions of Kenya

ABSTRACT The drug resistance profiles of Plasmodium falciparum isolated from four regions in Kenya were analyzed for drug resistance profiles. We observed variability in resistance to a broad range of antimalarial drugs across Kenya as determined from in vitro drug susceptibility screening and genotyping analysis.

Epidemic infectious gastrointestinal illness aboard U.S. Navy ships deployed to the Middle East during peacetime operations--2000-2001.

BackgroundInfectious gastrointestinal illness (IGI) outbreaks have been reported in U.S. Navy ships and could potentially have an adverse mission impact. Studies to date have been anecdotal.MethodsWe conducted a retrospective analysis of weekly reported disease and non-battle injury health data collected in 2000 – 2001 from 44 U.S. Navy ships while sailing in the 5th Fleet (Persian Gulf and nearby seas).ResultsDuring this period, 11 possible IGI outbreaks were identified. Overall, we found 3.3 outbreaks per 100 ship-weeks, a mean outbreak duration of 4.4 weeks, and a mean cumulative ship population attack rate of 3.6%. Morbidity, represented by days lost due to personnel being placed on sick-in-quarters status, was higher during outbreak weeks compared to non-outbreak weeks (p = 0.002). No clear seasonal distribution was identified.ConclusionExplosive outbreaks due to viruses and bacteria with the potential of incapacitating large proportions of the crew raise serious concerns of mission impact and military readiness.

Experience of a global laboratory network in responding to infectious disease epidemics.

The challenge of emerging infections transcends national borders. Influenza A (H5N1) severe acute respiratory syndrome (SARS) and diseases that continue to re-emerge such as cholera drug-resistant malaria and dengue can expand rapidly from local to regional or global threats. We were pleased to see that Georgios Pappas and colleagues in their global review of human brucellosis epidemiology discussed serious problems in tracking and containing the disease which apply to many emerging infections: lack of appropriate diagnostic capabilities in developing countries cross-border disease spread from countries with high incidence and emergence of new endemic foci because of socioeconomic and other changes. Several of us have proposed a network of new broad-based laboratories as a way to address such challenges for emerging infections of international importance. These laboratories would assist host countries in developing surveillance systems and responding to epidemics strengthen global epidemic detection and response efforts of WHO in key regions and form links with specialised institutions worldwide to support these activities. (excerpt)