MERS-CoV seroconversion amongst Malaysian Hajj pilgrims returning from the Middle East, 2016-2018: results from the MERCURIAL multiyear prospective cohort study.

Prospective cohort study to investigate the potential exposure to the Middle East Respiratory Syndrome-Coronavirus (MERS-CoV) following Hajj pilgrims is still very limited. Here, we report the antibody seroconversion study results obtained from successive three years cohort studies (2016-2018) involving the Malaysian Hajj pilgrims returning from the Middle East. A cohort study of Hajj pilgrims from Malaysia enrolled 2,863 participants from 2016-2018, all of whom consented to provide paired blood samples for both pre- and post-Hajj travel to the Middle East. ELISAs and micro-neutralization assays were performed to detect the presence of MERS-CoV IgG antibodies. Sociodemographic data, symptoms experienced during Hajj, and history of exposure to camels or camel products were recorded using structured pre- and post-Hajj questionnaires. A 4-fold increase in anti-MERS-CoV IgG between paired pre-Hajj and post-Hajj serum samples in twelve participants was observed. None of the twelve ELISA-positive sera had detectable levels of virus-neutralizing antibodies. All reportedly had mild symptoms of respiratory symptoms at a certain point during the pilgrimage, implying mild or asymptomatic infections. No association between post-Hajj serum positivity and a history of exposure to camels or camel products was obtained. Findings from the study suggest that serologic conversion to MERS-CoV occurred in at least 0.6% of the Hajj pilgrims returning from the Middle East. Since all the seroconvertants had mild to no symptoms during the sampling period, it highlights the likelihood of occurrence of only low infectivity spillover infections among the Hajj pilgrims.

Genomic and virologic characterization of samples from a shipboard outbreak of COVID-19 reveals distinct variants within limited temporospatial parameters.

Early in the pandemic, in March of 2020, an outbreak of COVID-19 occurred aboard the aircraft carrier USS Theodore Roosevelt (CVN-71), during deployment in the Western Pacific. Out of the crew of 4,779 personnel, 1,331 service members were suspected or confirmed to be infected with SARS-CoV-2. The demographic, epidemiologic, and laboratory findings of service members from subsequent investigations have characterized the outbreak as widespread transmission of virus with relatively mild symptoms and asymptomatic infection among mostly young healthy adults. At the time, there was no available vaccination against COVID-19 and there was very limited knowledge regarding SARS-CoV-2 mutation, dispersal, and transmission patterns among service members in a shipboard environment. Since that time, other shipboard outbreaks from which data can be extracted have occurred, but these later shipboard outbreaks have occurred largely in settings where the majority of the crew were vaccinated, thereby limiting spread of the virus, shortening duration of the outbreaks, and minimizing evolution of the virus within those close quarters settings. On the other hand, since the outbreak on the CVN-71 occurred prior to widespread vaccination, it continued over the course of roughly two months, infecting more than 25% of the crew. In order to better understand genetic variability and potential transmission dynamics of COVID-19 in a shipboard environment of immunologically naïve, healthy individuals, we performed whole-genome sequencing and virus culture from eighteen COVID-19-positive swabs collected over the course of one week. Using the unique variants identified in those genomes, we detected seven discrete groups of individuals within the population aboard CVN-71 infected with viruses of distinct genomic signature. This is in stark contrast to a recent outbreak aboard another U.S. Navy ship with >98% vaccinated crew after a port visit in Reykjavik, Iceland, where the outbreak lasted only approximately 2 weeks and the virus was clonal. Taken together, these results demonstrate the utility of sequencing from complex clinical samples for molecular epidemiology and they also suggest that a high rate of vaccination among a population in close communities may greatly reduce spread, thereby restricting evolution of the virus.

Cohort profile: a migratory cohort study of US Marines who train in Australia.

PURPOSE: In 2012, US Marines and Sailors began annual deployments to Australia to participate in joint training exercises with the Australian Defence Force and other partners in the region. During their training, US service members are exposed to a variety of infectious disease threats not normally encountered by American citizens. This paper describes a cohort of US Marines and Sailors enrolled during five rotations to Australia between 2016 and 2020. PARTICIPANTS: Study participation is strictly voluntary. Group informational sessions are held prior to deployment to describe the study structure and goals, as well as the infectious disease threats that participants may encounter while in Australia. All participants provided written informed consent. Consented participants complete a pre-deployment questionnaire to collect data including basic demographic information, military occupational specialty, travel history, family history, basic health status and personal habits such as alcohol consumption. Blood is collected for serum, plasma and peripheral blood mononuclear cells (PBMC) processing. Data and specimen collection is repeated up to three times: before, during and after deployment. FINDINGS TO DATE: From the five rotations that comprised the 2016-2020 Marine Rotational Force-Darwin, we enrolled 1289 volunteers. Enrolments during this period were overwhelmingly white male under the age of 24 years. Most of the enrollees were junior enlisted and non-commissioned officers, with a smaller number of staff non-commissioned officers and commissioned officers, and minimal warrant officers. Over half of the enrollees had occupational specialty designations for infantry. FUTURE PLANS: In the future, we will screen samples for serological evidence of infection with Burkholderia pseudomallei, Coxiella burnetii, Ross River virus, SARS-CoV-2 and other operationally relevant pathogens endemic in Australia. Antigenic stimulation assays will be performed on PBMCs collected from seropositive individuals to characterise the immune response to these infections in this healthy American population.

Multiyear prospective cohort study to evaluate the risk potential of MERS-CoV infection among Malaysian Hajj pilgrims (MERCURIAL): a study protocol.

INTRODUCTION: Middle East respiratory syndrome (MERS) is a viral respiratory infection caused by the MERS-CoV. MERS was first reported in the Kingdom of Saudi Arabia in 2012. Every year, the Hajj pilgrimage to Mecca attracts more than two million pilgrims from 184 countries, making it one of the largest annual religious mass gatherings (MGs) worldwide. MGs in confined areas with a high number of pilgrims' movements worldwide continues to elicit significant global public health concerns. MERCURIAL was designed by adopting a seroconversion surveillance approach to provide multiyear evidence of MG-associated MERS-CoV seroconversion among the Malaysian Hajj pilgrims. METHODS AND ANALYSIS: MERCURIAL is an ongoing multiyear prospective cohort study. Every year, for the next 5 years, a cohort of 1000 Hajj pilgrims was enrolled beginning in the 2016 Hajj pilgrimage season. Pre-Hajj and post-Hajj serum samples were obtained and serologically analysed for evidence of MERS-CoV seroconversion. Sociodemographic data, underlying medical conditions, symptoms experienced during Hajj pilgrimage, and exposure to camel and untreated camel products were recorded using structured pre-Hajj and post-Hajj questionnaires. The possible risk factors associated with the seroconversion data were analysed using univariate and multivariate logistic regression. The primary outcome of this study is to better enhance our understanding of the potential threat of MERS-CoV spreading through MG beyond the Middle East. ETHICS AND DISSEMINATION: This study has obtained ethical approval from the Medical Research and Ethics Committee (MREC), Ministry of Health Malaysia. Results from the study will be submitted for publication in peer-reviewed journals and presented in conferences and scientific meetings. TRIAL REGISTRATION NUMBER: NMRR-15-1640-25391.

Antibody Responses to SARS-CoV-2 Following an Outbreak Among Marine Recruits With Asymptomatic or Mild Infection.

We investigated serological responses following a SARS-CoV-2 outbreak in spring 2020 on a US Marine recruit training base. 147 participants that were isolated during an outbreak of respiratory illness were enrolled in this study, with visits approximately 6 and 10 weeks post-outbreak (PO). This cohort is comprised of young healthy adults, ages 18-26, with a high rate of asymptomatic infection or mild symptoms, and therefore differs from previously reported longitudinal studies on humoral responses to SARS-CoV-2, which often focus on more diverse age populations and worse clinical presentation. 80.9% (119/147) of the participants presented with circulating IgG antibodies against SARS-CoV-2 spike (S) receptor-binding domain (RBD) at 6 weeks PO, of whom 97.3% (111/114) remained positive, with significantly decreased levels, at 10 weeks PO. Neutralizing activity was detected in all sera from SARS-CoV-2 IgG positive participants tested (n=38) at 6 and 10 weeks PO, without significant loss between time points. IgG and IgA antibodies against SARS-CoV-2 RBD, S1, S2, and the nucleocapsid (N) protein, as well neutralization activity, were generally comparable between those participants that had asymptomatic infection or mild disease. A multiplex assay including S proteins from SARS-CoV-2 and related zoonotic and human endemic betacoronaviruses revealed a positive correlation for polyclonal cross-reactivity to S after SARS-CoV-2 infection. Overall, young adults that experienced asymptomatic or mild SARS-CoV-2 infection developed comparable humoral responses, with no decrease in neutralizing activity at least up to 10 weeks after infection.

SARS-CoV-2 Transmission among Marine Recruits during Quarantine.

BACKGROUND: The efficacy of public health measures to control the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has not been well studied in young adults. METHODS: We investigated SARS-CoV-2 infections among U.S. Marine Corps recruits who underwent a 2-week quarantine at home followed by a second supervised 2-week quarantine at a closed college campus that involved mask wearing, social distancing, and daily temperature and symptom monitoring. Study volunteers were tested for SARS-CoV-2 by means of quantitative polymerase-chain-reaction (qPCR) assay of nares swab specimens obtained between the time of arrival and the second day of supervised quarantine and on days 7 and 14. Recruits who did not volunteer for the study underwent qPCR testing only on day 14, at the end of the quarantine period. We performed phylogenetic analysis of viral genomes obtained from infected study volunteers to identify clusters and to assess the epidemiologic features of infections. RESULTS: A total of 1848 recruits volunteered to participate in the study; within 2 days after arrival on campus, 16 (0.9%) tested positive for SARS-CoV-2, 15 of whom were asymptomatic. An additional 35 participants (1.9%) tested positive on day 7 or on day 14. Five of the 51 participants (9.8%) who tested positive at any time had symptoms in the week before a positive qPCR test. Of the recruits who declined to participate in the study, 26 (1.7%) of the 1554 recruits with available qPCR results tested positive on day 14. No SARS-CoV-2 infections were identified through clinical qPCR testing performed as a result of daily symptom monitoring. Analysis of 36 SARS-CoV-2 genomes obtained from 32 participants revealed six transmission clusters among 18 participants. Epidemiologic analysis supported multiple local transmission events, including transmission between roommates and among recruits within the same platoon. CONCLUSIONS: Among Marine Corps recruits, approximately 2% who had previously had negative results for SARS-CoV-2 at the beginning of supervised quarantine, and less than 2% of recruits with unknown previous status, tested positive by day 14. Most recruits who tested positive were asymptomatic, and no infections were detected through daily symptom monitoring. Transmission clusters occurred within platoons. (Funded by the Defense Health Agency and others.).

Distribution of Capsular Types of Campylobacter jejuni Isolates from Symptomatic and Asymptomatic Children in Peru.

Campylobacter jejuni is the leading bacterial cause of diarrhea worldwide. A capsular polysaccharide (CPS) conjugate vaccine is under development and requires determination of the valency. However, distribution of CPS types circulating globally is presently poorly described. We aimed to determine whether CPS type distribution in Peru differs from that in other endemic regions. We used a multiplex polymerase chain reaction (PCR) assay for the detection of CPS encoding genes capable of distinguishing all 35 CPS types on Campylobacter isolates in two prospective communities based studies conducted in cohorts of children less than 59 months of age in Peru. Results showed that CPS type HS4 complex was the most prevalent, followed by HS3 complex and HS15. Differences in CPS type for symptomatology were not statistically significant. Most subjects demonstrated repeated infections over time with different CPS types, suggesting that CPS types may confer of a level of homologous protective immunity. In this dataset, some differences in CPS type distribution were observed in comparison to other low-middle income countries. Further studies need to be conducted in endemic areas to increase our knowledge of CPS type distribution and guide vaccine development.

Seroprevalence of Borrelia burgdorferi among the indigenous people (Orang Asli) of Peninsular Malaysia.

INTRODUCTION: Lyme disease has been well-described in the North America and European countries. However, information is still very limited in the developing countries including Malaysia. The Orang Asli (OA), the indigenous people of Peninsular Malaysia reside mostly in the forest and forest fringe areas abundant with the vector for Lyme disease. Here, we described the seroprevalence of Borellia burgdorferi (B. burgdorferi) among the OA and demographic variables that could be associated with seroprevalence. METHODOLOGY: A total of 16 OA villages distributed across 8 states in Peninsular Malaysia participated in this study. Sera obtained from 904 OA volunteers were screened for anti-B. burgdorferi IgG antibodies. ELISA results obtained and demographic information collected were analysed to identify possible variables associated with seroprevalence. RESULTS: A total of 73 (8.1%) OA tested positive for anti-B. burgdorferi IgG antibodies. Among all the variables examined, village of residence (p = 0.045) was the only significant predictor for seropositivity. High (> 10.0%) prevalence was associated with three OA villages. Those living in one particular village were 1.65 times more likely to be seropositive as compared to other OA villages. Age, gender, marital status, household size, level of education, monthly household income and occupation were not significant predictors for seropositivity. CONCLUSION: Results of the present study support earlier findings that B. burgdorferi infection among Malaysians is currently under-recognized. Further studies will be needed at these locations to confirm the presence of Lyme disease among these populations.

Seroprevalence of Q Fever Among the Indigenous People (Orang Asli) of Peninsular Malaysia.

Q fever is a disease caused by Coxiella burnetii. It is a disease of public health concern in many parts of the world. In this study, we described the seroprevalence of Q fever among selected populations of Orang Asli (OA), indigenous people, many of whom live within the forest fringe areas of Peninsular Malaysia. Serum samples were obtained from 887 OA participants from selected villages. Samples were analyzed for the presence of IgG antibodies reactive against C. burnetii by enzyme-linked immunosorbent assay. Statistical methods were used to identify possible associations between seropositivity for C. burnetii and a number of demographic variables obtained from the questionnaires. In total, 9.6% (n = 85/887) of the serum samples were reactive to C. burnetii. Statistical results suggest that elderly male OA residing in OA village, Bukit Payung, were most likely to be tested seropositive for C. burnetii. This study suggests that OA are at a significant risk of contracting C. burnetii infection, and both demographic and geographic factors are important contributors to this risk. Further prospective studies are needed to establish the true burden of C. burnetii infection within the indigenous population as well as within Peninsular Malaysia as a whole.

Chymase Level Is a Predictive Biomarker of Dengue Hemorrhagic Fever in Pediatric and Adult Patients.

Background: Most patients with dengue experience mild disease, dengue fever (DF), while few develop the life-threatening diseases dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS). No laboratory tests predict DHF or DSS. We evaluated whether the serum chymase level can predict DHF or DSS in adult and pediatric patients and the influence of preexisting conditions (PECs) on chymase levels. Methods: Serum chymase levels were measured in patients presenting with undifferentiated fever to hospitals in Colombo District, Sri Lanka. The value of serum the chymase concentration and clinical signs and symptoms as predictors of DHF and/or DSS was evaluated by multivariate analysis. We assessed the influence of age, PECs, and day after fever onset on the robustness of the chymase level as a biomarker for DHF and/or DSS. Results: An elevated chymase level in acute phase blood samples was highly indicative of later diagnosis of DHF or DSS for pediatric and adult patients with dengue. No recorded PECs prevented an increase in the chymase level during DHF. However, certain PECs (obesity and cardiac or lung-associated diseases) resulted in a concomitant increase in chymase levels among adult patients with DHF. Conclusions: These results show that patients with acute dengue who present with high levels of serum chymase consistently are at greater risk of DHF. The chymase level is a robust prognostic biomarker of severe dengue for adult and pediatric patients.

Coxiella Detection in Ticks from Wildlife and Livestock in Malaysia.

Recent studies have shown that ticks harbor Coxiella-like bacteria, which are potentially tick-specific endosymbionts. We recently described the detection of Coxiella-like bacteria and possibly Coxiella burnetii in ticks found from rural areas in Malaysia. In the present study, we collected ticks, including Haemaphysalis bispinosa, Haemaphysalis hystricis, Dermacentor compactus, Dermacentor steini, and Amblyomma sp. from wildlife and domesticated goats from four different locations in Malaysia. Coxiella 16s rRNA genomic sequences were detected by PCR in 89% of ticks tested. Similarity analysis and phylogenetic analyses of the 16s rRNA and rpoB partial sequences were performed for 10 representative samples selected based on the tick species, sex, and location. The findings here suggested the presence of C. burnetii in two samples, each from D. steini and H. hystricis. The sequences of both samples clustered with published C. burnetii sequences. The remaining eight tick samples were shown to harbor 16s rRNA sequences of Coxiella-like bacteria, which clustered phylogenetically according to the respective tick host species. The findings presented here added to the growing evidence of the association between Coxiella-like bacteria and ticks across species and geographical boundaries. The importance of C. burnetii found in ticks in Malaysia warrants further investigation.

Norovirus: new developments and implications for travelers' diarrhea.

Noroviruses are the leading cause of acute gastroenteritis in the United States and are responsible for at least 50 % of acute gastroenteritis outbreaks occurring worldwide each year. In addition, noroviruses have caused outbreaks on cruise ships, in nursing homes and hospitals, and in deployed military personnel, but its role in the etiology of travelers' diarrhea is not well defined. The aim of this review is to describe the role of noroviruses in travelers' diarrhea in terms of epidemiology, current diagnostics, treatment and vaccine development efforts. Studies have shown prevalence rates of noroviruses in travelers' diarrhea cases ranging from 10-65 %. It is likely that norovirus prevalence rates are highly underestimated in travelers' diarrhea due to rapid onset, short duration of the illness, limited availability of laboratory facilities, and the fact that most clinical laboratories lack the diagnostic capability to detect noroviruses in stool. Further, additional studies are needed to accurately determine the true prevalence rates of norovirus as an etiologic agent of diarrhea among travelers to different regions around the world. With the rapid progress in the development of a norovirus vaccine, travelers could serve as an ideal population for future norovirus clinical trials.

Immunological Biomarkers in Postinfectious Irritable Bowel Syndrome.

BACKGROUND: There is a recognized need for biological markers to facilitate diagnoses of irritable bowel syndrome (IBS) and to distinguish it from other functional and organic disorders. As postinfectious IBS (PI-IBS) is believed to account for as many as one third of all IBS cases, here we sought to identify differences in specific cytokines and serologic responses across patients with idiopathic IBS and PI-IBS and healthy controls. METHODS: At total of 120 US military personnel were identified from the Defense Medical Surveillance System-based International Classification of Diseases, 9th Revision, Clinical Modification (ICD9-CM) codes recorded during medical encounters and were grouped based on infectious gastroenteritis (IGE) episode (Shigella, Campylobacter, Salmonella, or an unspecified pathogen) followed by IBS, IBS without antecedent IGE, or IGE without subsequent IBS within 2 years of the IGE exposure. Sera from subjects were assayed for cytokine levels and antibodies against a panel of microbiome antigens. RESULTS: In total, 10 of 118 markers considered were shown to differ between IBS patients and healthy controls, including cytokines interleukin-6 (IL-6), IL-8, IL-1ß, and macrophage inflammatory protein-1ß (MIP-1ß), as well as antibody responses to microbial antigens. Antimicrobial antibody response profiles also differed between PI-IBS cases compared with IBS cases without an antecedent episode of acute IGE. Comparisons also suggest that immunoglobulin A (IgA) and IgG profiles may point to pathogen-specific origins among PI-IBS cases. CONCLUSION: Taken together, these results provide further evidence as to the molecular distinctness of classes of IBS cases and that serum biomarkers may prove useful in elucidating their pathobiological pathways.

Global Distribution of Campylobacter jejuni Penner Serotypes: A Systematic Review.

Penner serotyping has been the principal method for differentiating Campylobacter isolates since its inception. Campylobacter capsule polysaccharide (CPS), the principal serodeterminant on which Penner serotyping is based, is presently of interest as a vaccine component. To determine the required valency of an effective CPS-based vaccine, a comprehensive understanding of CPS distribution is needed. Because of the association between Penner serotype and CPS, we conducted a systematic review to estimate the frequency and distribution of Penner serotypes associated with cases of Campylobacteriosis. In total, more than 21,000 sporadic cases of C. jejuni cases were identified for inclusion. While regional variation exists, distribution estimates indicate that eight serotypes accounted for more than half of all sporadic diarrheal cases globally and three serotypes (HS4 complex, HS2, and HS1/44) were dominant inter-regionally as well as globally. Furthermore, a total of 17 different serotypes reached a representation of 2% or greater in at least one of the five regions sampled. While this review is an important first step in defining CPS distribution, these results make it clear that significant gaps remain in our knowledge. Eliminating these gaps will be critical to future vaccine development efforts.

Acute gastroenteritis and the risk of functional dyspepsia: a systematic review and meta-analysis.

OBJECTIVES: The objective of this systematic review and meta-analysis was to estimate the risk of developing functional dyspepsia (FD) following acute infectious gastroenteritis (IGE). METHODS: Eligible studies were identified through PubMed and EMBASE searches. Data and quality indicators were extracted by two authors from nine studies examining the risk of FD following IGE in 5,755 exposed individuals. RESULTS: Estimates of FD risk following IGE based on a random effects model yielded a pooled odds ratio (OR) of 2.18 (95% confidence interval (CI): 1.70-2.81). Subanalyses revealed differences in the odds of FD following self-reported IGE (OR: 2.83, 95% CI: 2.10-3.81) compared with documented IGE medical encounters (OR: 1.81, 95% CI: 1.26-2.58), and a decreasing FD risk with time from IGE (≤12 months: OR: 4.76, 95% CI: 2.47-9.20 and >12 months: OR: 1.97, 95% CI: 1.51-2.56). CONCLUSIONS: Taken together, these data suggest that the risk of developing FD is significantly increased following IGE.

Failure to detect simian immunodeficiency virus infection in a large Cameroonian cohort with high non-human primate exposure.

Hunting and butchering of wildlife in Central Africa are known risk factors for a variety of human diseases, including HIV/AIDS. Due to the high incidence of human exposure to body fluids of non-human primates, the significant prevalence of simian immunodeficiency virus (SIV) in non-human primates, and hunting/butchering associated cross-species transmission of other retroviruses in Central Africa, it is possible that SIV is actively transmitted to humans from primate species other than mangabeys, chimpanzees, and/or gorillas. We evaluated SIV transmission to humans by screening 2,436 individuals that hunt and butcher non-human primates, a population in which simian foamy virus and simian T-lymphotropic virus were previously detected. We identified 23 individuals with high seroreactivity to SIV. Nucleic acid sequences of SIV genes could not be detected, suggesting that SIV infection in humans could occur at a lower frequency than infections with other retroviruses, including simian foamy virus and simian T-lymphotropic virus. Additional studies on human populations at risk for non-human primate zoonosis are necessary to determine whether these results are due to viral/host characteristics or are indicative of low SIV prevalence in primate species consumed as bushmeat as compared to other retroviruses in Cameroon.

High HIV type 1 group M pol diversity and low rate of antiretroviral resistance mutations among the uniformed services in Kinshasa, Democratic Republic of the Congo.

For the first time the genetic diversity among the uniformed personnel in Kinshasa, the capital city of the Democratic Republic of Congo (DRC), a country that has experienced military conflicts since 1998 and in which the global HIV-1/M pandemic started, has now been documented. A total of 94 HIV-1-positive samples, collected in 2007 in Kinshasa garrison settings from informed consenting volunteers, were genetically characterized in the pol region (protease and RT). An extensive diversity was observed, with 51% of the strains corresponding to six pure subtypes (A 23%, C 13.8%, D, G, H, J, and untypable), 15% corresponding to nine different CRFs (01, 02, 11, 13, 25, 26, 37, 43, and 45), and 34% being unique recombinants with one-third being complex mosaic viruses involving three or more different subtypes/CRFs. Only one strain harbored a single mutation, I54V, associated with drug resistance to protease inhibitors. Due to their high mobility and potential risk behavior, HIV infections in military personnel can lead to an even more complex epidemic in the DRC and to a possible increase of subtype C.

Major increase in human monkeypox incidence 30 years after smallpox vaccination campaigns cease in the Democratic Republic of Congo.

Studies on the burden of human monkeypox in the Democratic Republic of the Congo (DRC) were last conducted from 1981 to 1986. Since then, the population that is immunologically naïve to orthopoxviruses has increased significantly due to cessation of mass smallpox vaccination campaigns. To assess the current risk of infection, we analyzed human monkeypox incidence trends in a monkeypox-enzootic region. Active, population-based surveillance was conducted in nine health zones in central DRC. Epidemiologic data and biological samples were obtained from suspected cases. Cumulative incidence (per 10,000 population) and major determinants of infection were compared with data from active surveillance in similar regions from 1981 to 1986. Between November 2005 and November 2007, 760 laboratory-confirmed human monkeypox cases were identified in participating health zones. The average annual cumulative incidence across zones was 5.53 per 10,000 (2.18-14.42). Factors associated with increased risk of infection included: living in forested areas, male gender, age < 15, and no prior smallpox vaccination. Vaccinated persons had a 5.2-fold lower risk of monkeypox than unvaccinated persons (0.78 vs. 4.05 per 10,000). Comparison of active surveillance data in the same health zone from the 1980s (0.72 per 10,000) and 2006-07 (14.42 per 10,000) suggests a 20-fold increase in human monkeypox incidence. Thirty years after mass smallpox vaccination campaigns ceased, human monkeypox incidence has dramatically increased in rural DRC. Improved surveillance and epidemiological analysis is needed to better assess the public health burden and develop strategies for reducing the risk of wider spread of infection.

HIV type 1 pol gene diversity and genotypic antiretroviral drug resistance mutations in Malabo, Equatorial Guinea.

In this study, HIV strains circulating among military personnel were characterized, in Malabo, the capital city of Equatorial Guinea. One sample was found to be HIV-2 group A while a high degree of genetic diversity was recorded in the pol region of 41 HIV-1-positive samples. CRF02_AG accounted for 53.7% of the strains, and 11 different variants were obtained in the remaining 19 samples: subtype G (n = 3), A3 (n = 2), C (n = 2), CRF26_A5U (n = 2), F2 (n = 1), CRF06 (n = 1), CRF09 (n = 1), CRF11 (n = 1), CRF22 (n = 1), and divergent subtype A (n = 1) and F (n = 1). One strain could not be classified and three were unique recombinants. Analysis of antiretroviral drug resistance mutations revealed two patients each harboring one major mutation, M46I in protease and D67N in reverse transcriptase sequences, respectively. The high genetic diversity and emerging ARV resistance mutations call for frequent surveys and appropriate monitoring of ARV considering the increasing access to ARV in the country.

The origin and prevention of pandemics.

Despite the fact that most emerging diseases stem from the transmission of pathogenic agents from animals to humans, the factors that mediate this process are still ill defined. What is known, however, is that the interface between humans and animals is of paramount importance in the process. This review will discuss the importance of the human-animal interface to the disease emergence process. We also provide an overview of factors that are believed to contribute to the origin and global spread of emerging infectious diseases and offer suggestions that may serve as future prevention strategies, such as social mobilization, public health education, behavioral change, and communication strategies. Because there exists no comprehensive global surveillance system to monitor zoonotic disease emergence, the intervention measures discussed herein may prove effective temporary alternatives.