Detection of antibodies against Ornithodoros moubata salivary antigens and their association with detection of African swine fever virus in pigs slaughtered in central Uganda.

Introduction: African swine fever (ASF) is an important disease of pigs in sub-Saharan Africa and Uganda and is threatening the pig population and agricultural economy of other continents. ASF virus (ASFV) can be transmitted from wild suids to domestic pigs through soft ticks of the Ornithodoros species. The aim of this study was to understand the relationship between domestic pigs' O. moubata tick exposure and ASFV status. Methods: Pigs were sampled from six abattoirs in the Kampala metropolitan area of Uganda from May 2021 through June 2022. Blood, serum, and tissue samples were collected. Serum was tested for antibodies against the rtTSGP1 salivary antigens of O. moubata ticks using an indirect ELISA assay. Blood and tissue samples from pigs were tested to detect ASFV using qPCR. Probability of tick exposure was categorized based on sample-to-positive ratio cut-off points. Results: Out of 1,328 serum samples tested, there were 828 (62.3%) samples with a negligible probability; 369 (27.8%) with a medium probability; 90 (6.8%) with a high probability, and 41 (3.1%) with a very high probability of exposure to the O. moubata salivary antigen. There was a statistically significant association between the pigs' O. moubata exposure and ASFV status with a higher proportion of pigs having a very high probability of infection if they were ASFV positive by blood, tonsil, and lymph nodes. Discussion: These results suggested that tick exposure was associated with ASFV transmission in Uganda. There were ASFV qPCR positive pigs that had no O. moubata exposure as well, which highlights that pig-to-pig and indirect contact transmission still play a significant role. This work highlights the need for further work in Uganda to investigate these transmission factors related to the O. moubata tick and ASFV transmission.

Spatiotemporal description of African swine fever virus nucleic acid and antibodies detected in pigs sampled at abattoirs in the greater Kampala metropolitan area, Uganda from May 2021 through June 2022.

BACKGROUND: African swine fever virus (ASFV) infections in Africa cause hemorrhagic disease in domestic pigs and is maintained by a sylvatic cycle in warthogs. It is endemic in Uganda, leading to significant economic losses. Previous studies performed in rural areas and in Kampala had differing diagnostic results. The purpose of this study was to provide a robust spatial, temporal, and diagnostic summary of pigs slaughtered in the greater Kampala metropolitan area over the course of one year. This study characterized 1208 to 1323 serum, blood, and tissue samples collected from pigs at six abattoirs in the greater Kampala metropolitan area of Uganda monthly from May 2021 through June 2022. Validated and standardized serologic and molecular diagnostics were used. RESULTS: Only 0.15% of pigs had detectable antibodies against ASFV, suggesting low survival rates or pre-clinical diagnosis. Yet, 59.5% of pigs were positive for ASFV DNA. Blood had the lowest detection rate (15.3%) while tonsil and lymph nodes had the highest (38% and 37.5%, respectively), spleen samples (31.5%) were in between. Agreement between sample types was fair to moderate overall. A significant seasonality of ASFV infections emerged with infections found predominately in the dry seasons. Spatial assessments revealed that the greater Kampala metropolitan area abattoirs have a catchment area that overlaps with Uganda's most pig dense regions. CONCLUSIONS: Pigs at greater Kampala metropolitan area abattoirs can be sentinels for acute disease throughout the pig dense region of Uganda, particularly in the dry seasons. The high prevalence detected suggests that pigs are sold in response to local reports of ASFV infections (panic sales). Serological surveillance is not useful, as very few pigs seroconverted in this study prior to slaughter. In contrast, tissue samples of pigs can be used to detect disease using qPCR methods.

A survey of biosecurity practices of pig farmers in selected districts affected by African swine fever in Uganda.

Introduction: In Uganda, pig production is an important source of livelihood for many people and contributes to food security. African swine fever (ASF) is a major constraint to pig production in Uganda, threatening the food supply and sustainable livelihoods. Prevention of ASF primarily relies on good biosecurity practices along the pig value chain. Previous studies showed that biosecurity along the pig value chain and on farms in Uganda is poor. However, the biosecurity practices of pig farmers in ASF affected areas of Uganda and their opinions on on-farm ASF morbidity and mortality were previously not comprehensively characterized. The objectives of this study were to document pig farmers' experiences with ASF in their farms and to describe the pig biosecurity practices in districts of Uganda that were highly affected by ASF. Methods: A total of 99 farmers were interviewed in five districts. Data were collected by way of triangulation through farmer interviews, field observations during the farmer interviews, and a survey of key informants. However, farmer interviews were considered the primary source of data for this study. Farmers' biosecurity practices were scored using a biosecurity scoring algorithm. Results: Forty-one out of 96 (42.7%) farmers reported having pigs with ASF in the past 12 months. The level of pig farming experience (p = 0.0083) and herd size (p < 0.0001) were significantly associated with the reported occurrence of ASF. Overall, the biosecurity scores for the respondents were considered poor with 99% (98/99) scoring <70% and just one farmer obtaining a fair score of 72.2%. District (p = 0.0481), type of husbandry system (p = 0.014), and type of pig breed raised (p = 0.004) were significantly associated with farmer's biosecurity score. Conclusion: Continued farmer education on ASF and the importance of good biosecurity practices is necessary. More in-depth scientific inquiry into the factors influencing the biosecurity practices among pig farmers in Uganda is necessary.

The live pig supply chain as reported by farmers in selected districts affected by African swine fever in Uganda, June and July 2022.

Introduction: Uganda is a pork-producing country in East Africa. The African swine fever virus (ASFV) has had a devastating impact on the country's pig industry. The movements of pigs and pork are a major pathway of spreading ASFV. This study was done to describe the live pig supply chain within and through districts that are impacted by African swine fever (ASF) in Uganda. Methods: A pig farmer survey in districts known to have ASFV was done using a semi-structured questionnaire available in English and two local languages. In total, 99 farmers were interviewed across five districts. Farmers were conveniently and purposively selected by local government veterinary officials. An online key informant survey was also used to validate farmer responses. Results: Most farmers interviewed in all districts reported to source and sell most of their pigs from within their district the farm was in, although there was variation by district and pig type. In relation to pig type, 89.7% of farmers sourced sows, 80.0% sourced boars, and 96.4% sourced weaned pigs from the district where the farm was located. As for sales, 91.3% of farmers sold sows, 92.7% sold boars, 91.9% sold weaned pigs, and 92.2% sold market pigs in the district where the farm was located. There was also variation to whom pigs were sold and sourced by pig type. Conclusion: This information is useful when planning the scale and focus of disease control programs based on animal movement. This study revealed that pig disease control programs can be targeted to smaller regions. Furthermore, there is a need for farmers and pig traders to be educated on and adhere to veterinary regulations of animal movement and good biosecurity practices to reduce disease spread when purchasing and selling pigs from known ASFV infected areas.

Whole Genome Sequencing Shows that African Swine Fever Virus Genotype IX Is Still Circulating in Domestic Pigs in All Regions of Uganda.

Blood samples were collected from pigs at six abattoirs in the Kampala, Uganda metropolitan area from May 2021 through June 2022, and tested for African swine fever virus. Thirty-one samples with cycle threshold values < 26 from pigs with different geographic origins, clinical and pathologic signs, and Ornithodoros moubata exposure underwent whole genome sequencing. The p72 gene was used to genotype the isolates, and all were found to be genotype IX; whole genome sequences to previous genotype IX isolates confirmed their similarity. Six of the isolates had enough coverage to evaluate single nucleotide polymorphisms (SNPs). Five of the isolates differed from historic regional isolates, but had similar SNPs to one another, and the sixth isolate also differed from historic regional isolates, but also differed from the other five isolates, even though they are all genotype IX. Whole genome sequencing data provide additional detail on viral evolution that can be useful for molecular epidemiology, and understanding the impact of changes in genes to disease phenotypes, and may be needed for vaccine targeting should a commercial vaccine become available. More sequencing of African swine fever virus isolates is needed in Uganda to understand how and when the virus is changing.

Comparison of diaphragm meat juice and muscle swab samples to spleen and spleen swab samples for the detection of African swine fever viral nucleic acid.

Use of meat juice and muscle swabs at slaughterhouses may provide an easy-to-collect sample for African swine fever (ASF) surveillance. Meat juice has been experimentally shown to be a reliable sample for the detection of ASF virus (ASFV). We compared the detection of ASFV nucleic acid from diaphragm meat juice, diaphragm muscle swab, spleen, and spleen swabs from pigs with signs of ASFV infection at slaughterhouses around Kampala, Uganda. Pigs with ≥2 clinical or pathology signs at the time of slaughter had a spleen sample, spleen swab, diaphragm muscle sample, and diaphragm muscle swab collected. Meat juice was collected from muscle samples through a freeze-thaw cycle. Each sample was tested individually, and 72 spleen, meat juice, and muscle swab sample pools of 4 negative and 1 positive sample were tested, as well. Standard operating procedures from the USDA-Foreign Animal Disease Diagnostic Laboratory for viral DNA extraction and real-time PCR (rtPCR) were used. Of the 493 pigs evaluated, we classified as positive 357 (72.4%) diaphragm meat juice samples, 218 (44.2%) diaphragm muscle swabs, 247 (50.1%) spleen samples, and 241 (48.9%) spleen swabs. All spleen sample pools were positive (72 of 72; 100%), as were 71 of 72 (98.6%) meat juice pools and 67 of 72 (93.1%) muscle swab pools. Meat juice samples provided a reliable sample type for the detection by rtPCR of ASFV in pigs with natural infections.

An Investigation of Burkholderia pseudomallei Seroprevalence in Market Pigs Slaughtered at Selected Pig Abattoirs in Uganda.

Burkholderia pseudomallei is a Gram-negative bacterium that causes melioidosis, a disease of humans and animals. It is primarily transmitted through direct contact with contaminated soil and surface water. The epidemiology of this pathogen in Africa, including Uganda, is largely unknown. The objectives of this study were to estimate the seroprevalence of B. pseudomallei in pigs slaughtered in central Uganda and to identify potential hotspots for this pathogen in the country. A total of 1035 pig sera were analyzed for serological responses to B. pseudomallei with type A and type B LPS using OPS type A and OPS type B ELISAs. Of the 1035 samples, 75 (7.25%, 95% CI: 5.8-9%) were seropositive to the OPS-A ELISA using a two standard deviations (SD) cutoff and 19 (1.84%, 95% CI: 1.2-2.9%) at 3 SD. For the OPS-B ELISA, 93/1035 (8.99%, 95% CI: 7.4-10.9%) were seropositive at the 2 SD cutoff, and 28/1035 (2.71%, 95% CI: 1.9-3.9%) at the 3 SD cutoff. Pigs slaughtered in central Uganda were exposed to B. pseudomallei, and there is a higher seroprevalence in the rainy months. Public health awareness campaigns about melioidosis may be needed.

An Assessment of Diagnostic Assays and Sample Types in the Detection of an Attenuated Genotype 5 African Swine Fever Virus in European Pigs over a 3-Month Period.

African swine fever virus causes hemorrhagic disease in swine. Attenuated strains are reported in Africa, Europe, and Asia. Few studies on the diagnostic detection of attenuated ASF viruses are available. Two groups of pigs were inoculated with an attenuated ASFV. Group 2 was also vaccinated with an attenuated porcine reproductive and respiratory syndrome virus vaccine. Commercially available ELISA, as well as extraction and qPCR assays, were used to detect antibodies in serum and oral fluids (OF) and nucleic acid in buccal swabs, tonsillar scrapings, OF, and blood samples collected over 93 days, respectively. After 12 dpi, serum (88.9% to 90.9%) in Group 1 was significantly better for antibody detection than OF (0.7% to 68.4%). Group 1's overall qPCR detection was highest in blood (48.7%) and OF (44.2%), with the highest detection in blood (85.2%) from 8 to 21 days post inoculation (dpi) and in OF (83.3%) from 1 to 7 dpi. Group 2's results were not significantly different from Group 1, but detection rates were lower overall. Early detection of attenuated ASFV variants requires active surveillance in apparently healthy animals and is only reliable at the herd level. Likewise, antibody testing will be needed to prove freedom from disease.

Brucella suis and farm biosecurity: assessing risk in pigs raised outdoors in New York State.

OBJECTIVE: To evaluate the Brucella suis exposure status of pigs raised with outdoor access on farms in New York State and assess biosecurity and management practices of those farms. ANIMALS: 250 pigs that were raised for commercial purposes, had access to the outdoors, and were > 4 months of age on 24 farms in New York State. PROCEDURES: Farms were randomly selected from a sampling frame generated for the study and contacted to recruit them to participate. Participating farms were provided a questionnaire to complete. Up to 30 pigs per farm were tested for serum anti-Brucella antibodies. RESULTS: Farm were classified as seasonal and year round. Seasonal farms raised pigs for slaughter, and year-round farms bred pigs, raised them for slaughter, and sold live pigs to others to raise. None of the 250 pigs had antibodies to Brucella spp. Nevertheless, the biosecurity assessment revealed a need for enhanced practices in procurement and management of swine in a wide range of areas. CLINICAL RELEVANCE: There was no evidence for ongoing B suis infection on these swine farms in New York State, but biosecurity and preventive practices at these facilities could be improved to prevent the introduction and spread of B suis and other pathogens.

A Molecular and Epidemiological Description of a Severe Porcine Reproductive and Respiratory Syndrome Outbreak in a Commercial Swine Production System in Russia.

Porcine reproductive and respiratory syndrome (PRRS) is an economically devastating disease of swine in many parts of the world. Porcine reproductive and respiratory syndrome virus (PRRSV) type 1 is endemic in Europe, and prevalence of the subtypes differ spatially. In this study, we investigated a severe PRRS outbreak reported in 30 farms located in eastern Russia that belong to a large swine production company in the region that was also experiencing a pseudorabies outbreak in the system. Data included 28 ORF5 sequences from samples across 18 of the 25 infected sites, reverse transcriptase real-time polymerase chain reaction (RT-qPCR) results from diagnostic testing, reports of clinical signs, and animal movement records. We observed that the outbreak was due to two distinct variants of wildtype PRRSV type 1 subtype 1 with an average genetic distance of 15%. Results suggest that the wildtype PRRSV variants were introduced into the region around 2019, before affecting this production system (i.e., sow farms, nurseries, and finisher farms). Clinical signs did not differ between the variants, but they did differ by stage of pig production. Biosecurity lapses, including movement of animals from infected farms contributed to disease spread.

An assessment of enhanced biosecurity interventions and their impact on porcine reproductive and respiratory syndrome virus outbreaks within a managed group of farrow-to-wean farms, 2020-2021.

Introduction: Porcine reproductive and respiratory syndrome virus (PRRSV) has been a challenge for the U.S. swine industry for over 30 years, costing producers more than $600 million annually through reproductive disease in sows and respiratory disease in growing pigs. In this study, the impact of enhanced biosecurity practices of site location, air filtration, and feed mitigation was assessed on farrow-to-wean sites managed by a large swine production management company in the Midwest United States. Those three factors varied in the system that otherwise had implemented a stringent biosecurity protocol on farrow-to-wean sites. The routine biosecurity followed commonplace activities for farrow-to-wean sites that included but were not limited to visitor registration, transport disinfection, shower-in/shower-out procedures, and decontamination and disinfection of delivered items and were audited. Methods: Logistic regression was used to evaluate PRRSV infection by site based on the state where the site is located and air filtration use while controlling for other variables such as vaccine status, herd size, and pen vs. stall. A descriptive analysis was used to evaluate the impact of feed mitigation stratified by air filtration use. Results: Sites that used feed mitigates as additives in the diets, air filtration of barns, and that were in less swine-dense areas appeared to experience fewer outbreaks associated with PRRSV infection. Specifically, 23.1% of farms that utilized a feed mitigation program experienced PRRSV outbreaks, in contrast to 100% of those that did not. Sites that did not use air filtration had 20 times greater odds of having a PRRSV outbreak. The strongest protective effect was found when both air filtration and feed mitigation were used. Locations outside of Minnesota and Iowa had 98.5-99% lesser odds of infection as well. Discussion: Enhanced biosecurity practices may yield significant protective effects and should be considered for producers in swine-dense areas or when the site contains valuable genetics or many pigs.

Clinical Indicators of Moribundity in Swine Experimentally Inoculated with African Swine Fever Virus.

African swine fever virus (ASFV), the causative agent of African Swine Fever (ASF), is an infectious disease of swine that is associated with high rates of morbidity and mortality in naive populations. ASFV is challenging to work with in vitro and the in vivo immune response remains an active area of study. Vaccine development, pathogenesis, and diagnostic assay development studies often require use of live swine housed in high-containment laboratories. Studies of this type are intended to obtain key data yet must minimize the pain and distress experienced by the animals. To implement humane endpoints, pigs are ideally euthanatized by barbiturate overdose prior to death from ASFV infection, as the final stages of ASF can be clinically severe. However, due to the complex nature of ASFV pathogenesis, predicting when an infected animal will become moribund and require euthanasia is difficult. The current study was intended to aid in predicting the onset of moribundity in swine. Toward this end, we performed statistical analyses of historical health record data from 103 swine experimentally infected with ASFV. Regression analysis suggested that rectal temperature has potential utility as a marker for predicting moribundity, whereas viral strain and duration of survival after inoculation were significant risk factors for death due to disease rather than euthanasia.

Transboundary animal diseases as re-emerging threats - Impact on one health.

Transboundary animal diseases are those that can move through a population of animals and cause considerable economic and societal harm. Many have high mortality, and in low-income areas, can quickly destroy herds and flocks of agricultural animals. Although much of One Health, which sits at the intersection of human, animal, and environmental health, focuses on the zoonotic diseases, in fact transboundary animal diseases can harm both humans and the environment through robbing communities of livelihoods and nutrition, and creating environmental contamination through extensive carcass disposal requirements. Transboundary animal diseases continue to circulate in the world, predominantly in low-income regions or in areas with less than optimal biosecurity. This paper will review three prominent emerging and re-emerging transboundary animal diseases, describing their pathology and diagnostics, as well as economic and food security impacts, which are substantial. Attention to these devastating diseases should be a One Health priority.

The socioeconomic factors surrounding the initial emergence of peste des petits ruminants in Kenya, Uganda, and Tanzania from 2006 through 2008.

Peste des petits ruminants (PPR) is a devastating disease of small ruminants that significantly hinders productivity in endemic areas. Kenya, Uganda and Tanzania reported their first cases in each country between 2006 and 2008 despite the disease being present in the region (Ethiopia and Sudan) since the 1990s. The time leading up to the outbreaks involved refugee movements, drought, civil unrest, and resulted in increased animal mingling, movement and density in these regions. Refugee camps with animal source food demands and a robust informal economy further added to the development of animal mingling and movement as well. Once introduced, common pastoral migration lands and trade routes likely transported the disease throughout the region. This paper highlights why trade routes, refugee camps and areas of animal crowding during droughts should be targeted for interventions, monitoring and surveillance as part of PPR control in a region.

A post-infection serologic assessment of cattle herd immune status after a vesicular stomatitis outbreak and the agreement of antibody assays.

Vesicular stomatitis (VS) is a vesicular disease of horses, cattle, and pigs in the Western Hemisphere caused by viruses in the genus Vesiculovirus. Disease manifests as vesicles and erosions on the oral mucosa, teats, prepuce, and coronary band, and is similar in presentation to foot-and-mouth disease. Laboratory confirmation is therefore required. Conventional assays include competitive (c)ELISA and complement fixation (CF). The cELISA provides more accurate herd-level detection of VSV-exposed cattle, but may lack the ability to capture fluctuating antibody levels in individual animals. The CF assay can confirm newly infected animals because of its ability to detect antigen-antibody complexes, thus is considered to be indicative of IgM. We evaluated the immune status of 2 herds affected by VSV in 2014 by testing sera collected in June 2015. Two conventional assays were compared to a novel IgM-IgG ELISA. When sampled in 2015, both herds had detectable VSV-specific antibodies; 18% and 36% of animals tested by cELISA and 2% and 8% of animals tested by CF were positive. The novel IgM-IgG assay exhibited fair agreement (adjusted kappa score of 48) with the conventional assays, and should be evaluated further to assess its ability to replace the 2 separate assays with a single assay system, or for its ability to replace the CF assay as a more sensitive method for defining newly exposed animals.

Gunshot wounds in military working dogs in Operation Enduring Freedom and Operation Iraqi Freedom: 29 cases (2003-2009).

OBJECTIVE: To describe the patient population, injuries, and treatment received on the battlefield, and ultimate outcome of U.S. military working dogs that incurred gunshot wound (GSW) injury in Operation Enduring Freedom (Afghanistan) or Operation Iraqi Freedom (Iraq). DESIGN: Retrospective study between January 2003 and December 2009. ANIMALS: Twenty-nine military working dogs from the U.S. military with confirmed GSW injuries incurred in combat in Operation Enduring Freedom or Operation Iraqi Freedom. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Clinical data from battlefield treatment, which includes care from the point of injury through arrival to, but not including, a designated veterinary treatment facility. Twenty-nine dogs were injured between 2003 and 2009. All but one of the injuries were from high caliber, high velocity weapons. Of the 29 injured dogs, 11 survived the injuries and 18 died (38% survival rate). Of the dogs that died, all but 1 died from catastrophic nonsurvivable injuries before treatment or evacuation could be instituted. The thorax was the most common site of injury (50%) followed by extremity wounds (46%). The leading cause of death from GSWs was from thoracic wounds, followed by head wounds. Dogs with extremity wounds as their only injury were most likely to survive, and dogs with multiple injuries were least likely to survive. All surviving dogs received treatment at the point of injury by military medics and dog handlers consistent with Tactical Combat Casualty Care guidelines for combat injuries in human service members. Of the 11 that survived, all dogs returned to full duty with subsequent deployment to combat zones. Location of wounds and injury severity at the time of presentation to veterinary care was not correlated with length of time until return to duty.

Puumala hantavirus outbreak among U.S. military health care beneficiaries, Stuttgart, Germany--2012.

Hantaviruses are viruses of the family Bunyaviridae that are transmitted to humans via inhalation of the aerosolized excrement of rodents. The geographic distribution of hantavirus includes the Americas, Asia, and Europe. An outbreak of Puumala hantavirus infections among U.S. military health care beneficiaries was identified by the U.S. Army Public Health Command Region-Europe at U.S. Army installations in Stuttgart, Germany, during 2012. Overall, five cases (one probable and four confirmed) were identified in three service members, one U.S. civilian employee, and one dependent family member. Four cases were hospitalized, one of whom required dialysis. The outbreak investigation revealed that all cases exercised in forested areas and most were active smokers (4 out of 5). This report reviews the types of hantaviruses found worldwide and suggests that health care providers should suspect and consider possible hantavirus infections when evaluating patients with histories and clinical presentations consistent with such infections.

The human-animal interface of domestic livestock management and production and its relationship to brucellosis in the country of Georgia 2010: a rapid assessment analysis.

CONTEXT: Brucellosis is endemic in the country of Georgia, with the highest incidence of disease in the east of Georgia, in the Kakheti region--which is also home to the majority of sheep and a large portion of the national cattle herd (two species that are natural hosts of zoonotic Brucella spp.). OBJECTIVE: Our purpose was to understand the ruminant livestock management and dairy production as well as the sociological factors in order to relate it to the disease ecology of brucellosis and to understand the framework that contributes too brucellosis transmission in the region. METHODS: In 2010, we examined the aspects of livestock management and production through the use of a semi-structured questionnaire that was administered to 198 villagers and 41 key informants (physicians, veterinarians, dairy production specialists, and laboratory personnel) who were identified by convenience sampling. Results were primarily qualitative, but some were quantified to reveal trends and compared with non-parametric tests. RESULTS: We found that animals are managed at the village level. Male villagers take turns shepherding and herding on both summer pastures (highlands) and winter pastures (lowlands or around the village). Men also do all the sheep-dairy production. Women care for milk cattle as well as make the dairy products from cow milk. Of the households that own livestock, 28% own sheep (50 per flock) and 96% own cattle (3 per herd). The northern-most part of Kakheti (Akhmeta) has the widest distribution of its cheese; the guda cheese from this area is sold all over Kakheti and central Georgia. Typically, cheese is aged in 20% brine for 3d (white cheeses) or 21d (guda cheeses). In addition, raw milk is used for cheese production and heating the milk is believed to decrease the quality of the final product. CONCLUSIONS: Interventions at the animal level will be best carried out in the fall when animals return to winter pastures. Under-employed private veterinarians would be available for extension work and contact with local villagers. Control will be best achieved at the animal level because the local people have a social and cultural resistance to the use of heated or pasteurized milk for cheese production.

A comparison of the serological evidence of Coxiella burnetii exposure between military working dogs and feral canines in Iraq.

Coxiella burnetii is the causative agent of the zoonotic disease Q fever. Military working dogs (MWDs) are exposed to disease while deployed and are a potential source for human infection. This study assesses the exposure of MWDs via postdeployment antibody serology. In 2007 and 2008, 115 deployed MWDs and 165 feral Iraqi canines had blood samples taken and evaluated for antibodies to C. burnetii. None of the MWDs seroconverted, alleviating the need to consider predeployment titers, while 5.5% of feral canines seroconverted. This difference was significant with a p value of <0.05. MWD vector control measures and prophylactic doxycycline administration are effective in Q fever disease control and prevention. Thus, MWDs may be less effective as sentinels for human populations in regards to tickborne diseases caused by C. burnetii. Nonetheless, veterinarians presented with an MWD with a fever of unknown origin should consider C. burnetii if the dog has recently redeployed, and if diagnosed should make the kennel master and medical treatment facility aware of the zoonotic risk.

Dual prenylation is required for Rab protein localization and function.

The majority of Rab proteins are posttranslationally modified with two geranylgeranyl lipid moieties that enable their stable association with membranes. In this study, we present evidence to demonstrate that there is a specific lipid requirement for Rab protein localization and function. Substitution of different prenyl anchors on Rab GTPases does not lead to correct function. In the case of YPT1 and SEC4, two essential Rab genes in Saccharomyces cerevisiae, alternative lipid tails cannot support life when present as the sole source of YPT1 and SEC4. Furthermore, our data suggest that double geranyl-geranyl groups are required for Rab proteins to correctly localize to their characteristic organelle membrane. We have identified a factor, Yip1p that specifically binds the di-geranylgeranylated Rab and does not interact with mono-prenylated Rab proteins. This is the first demonstration that the double prenylation modification of Rab proteins is an important feature in the function of this small GTPase family and adds specific prenylation to the already known determinants of Rab localization.