Outbreak of gastrointestinal anthrax following eating beef of suspicious origin: Isingiro District, Uganda, 2017

Lysins as a powerful alternative to combat Bacillus anthracis

This review gathers all, to the best of our current knowledge, known lysins, mainly bacteriophage-derived, that have demonstrated activity against Bacillus anthracis strains. B. anthracis is a spore-forming, toxin-producing bacteria, naturally dwelling in soil. It is best known as a potential biowarfare threat, an etiological agent of anthrax, and a severe zoonotic disease. Anthrax can be treated with antibiotics (ciprofloxacin, penicillin, doxycycline); however, their administration may take up even to 60 days, and different factors can compromise their effectiveness. Bacterial viruses, bacteriophages (phages), are natural enemies of bacteria and use their lytic enzymes, endolysins (lysins), to specifically kill bacterial cells. Harnessing the potential of lysins to combat bacterial infections holds promise for diminishing antibiotic usage and, consequently, addressing the escalating antibiotic resistance in bacteria. In this context, we list the lysins with the activity against B. anthracis, providing a summary of their lytic properties in vitro and the outcomes observed in animal models. Bacillus cereus strain ATCC 4342/RSVF1, a surrogate for B. anthracis, was also included as a target bacteria. KEY POINTS: • More than a dozen different B. anthracis lysins have been identified and studied. • They fall into three blocks regarding their amino acid sequence similarity and most of them are amidases. • Lysins could be used in treating B. anthracis infections.

One Health intervention for elimination of anthrax in an endemic district of Odisha: A baseline and endline study

Background

This study was to compare a baseline and endline survey which were conducted to assess the changes in knowledge, attitude and practices about anthrax disease among the communities after One Health intervention for the elimination of human anthrax in an endemic district of Odisha.

Methods

A total of 2670 respondents were interviewed during the baseline and 2511 for the endline survey using a structured questionnaire by multi-stage sampling method. Descriptive statistics were used and logistic regression was performed to estimate the relationship between the variables and knowledge of anthrax.

Results

Out of the total participants in the study, males were about 76.25% in baseline and 72.08% in endline and about half of the total respondents were illiterate. Majority of the respondents had reported agriculture as their main occupation during both surveys. More than 50% of the respondents had livestock in their houses and farming was the main purpose for keeping them in both surveys. Around 20.26% of respondents knew about anthrax in baseline which raised to 53.64% after One Health intervention. Almost 21.29% of livestock owners had vaccinated their animals against anthrax disease throughout baseline, which increased to 66.5% during the endline survey.

Conclusion

This study highlights a significant surge in both knowledge and practices related to anthrax within the community after the implementation of intervention packages based on the One Health approach. The outcome of our study signified the importance of One Health interventions to address the health challenges related to zoonotic diseases in tribal communities. The data could be useful for local Governments to incorporate such an approach in their health policy to eliminate human anthrax.

Human Exposure to Naturally Occurring Bacillus anthracis in the Kars Region of Eastern Türkiye

Environmental contamination with Bacillus anthracis spores poses uncertain threats to human health. We undertook a study to determine whether inhabitants of the anthrax-endemic region of Kars in eastern Türkiye could develop immune responses to anthrax toxins without recognised clinical infection. We measured anti-PA and anti-LF IgG antibody concentrations by ELISA in serum from 279 volunteers, 105 of whom had previously diagnosed anthrax infection (100 cutaneous, 5 gastrointestinal). Of the 174 without history of infection, 72 had prior contact with anthrax-contaminated material. Individuals were classified according to demographic parameters, daily working environment, and residence type. All villages in this study had recorded previous animal or human anthrax cases. Stepwise regression analyses showed that prior clinical infection correlated strongly with concentrations at the upper end of the ranges observed for both antibodies. For anti-PA, being a butcher and duration of continuous exposure risk correlated with high concentrations, while being a veterinarian or shepherd, time since infection, and town residence correlated with low concentrations. For anti-LF, village residence correlated with high concentrations, while infection limited to fingers or thumbs correlated with low concentrations. Linear discriminant analysis identified antibody concentration profiles associated with known prior infection. Profiles least typical of prior infection were observed in urban dwellers with known previous infection and in veterinarians without history of infection. Four individuals without history of infection (two butchers, two rural dwellers) had profiles suggesting unrecognised prior infection. Healthy humans therefore appear able to tolerate low-level exposure to environmental B. anthracis spores without ill effect, but it remains to be determined whether this exposure is protective. These findings have implications for authorities tasked with reducing the risk posed to human health by spore-contaminated materials and environments.

Food safety incidents in the red meat industry: A review of foodborne disease outbreaks linked to the consumption of red meat and its products, 1991 to 2021

Red meat is a significant source of human nutrition, and the red meat industry contributes to the economy of nations. Nonetheless, there is a widespread global concern about public health issues posed by severe food safety incidents within the red meat industry. Most of these incidents are associated with foodborne disease outbreaks that impact individual consumers, food businesses and society. This study adopts a systematic search and review approach to identify three decades of published investigation reports of global foodborne disease outbreaks linked with the consumption of red meat and products made from them. The review aims to evaluate the critical features of these outbreak incidents to get insight into their contributing factors and root causes. In particular, this review discusses the transmission setting (origin of pathogenic agents), the food vehicles mostly incriminated, the causative pathogens (bacteria, viruses, and parasites) causing the most illnesses, and the most commonly reported contributing factors to the outbreaks. This information can help researchers and food business operators (FBOs) inform future risk assessment studies and support risk management activities in developing risk-mitigating strategies for the industry. Findings from this study suggest that implementing food safety management strategies which include adequate control measures at all stages of the food chain, from farm to fork, is imperative in preventing outbreak incidents. Of equal importance is the need for enhanced and sustained public education about the risk of foodborne illnesses associated with meat and its products whilst discouraging the consumption of raw meat products, especially by high-risk groups.

Informing One Health Anthrax Surveillance and Vaccination Strategy from Spatial Analysis of Anthrax in Humans and Livestock in Ha Giang Province, Vietnam (1999-2020)

Anthrax, caused by Bacillus anthracis, has a nearly global distribution but is understudied in Southeast Asia, including Vietnam. Here, we used historical data from 1999 to 2020 in Ha Giang, a province in northern Vietnam. The objectives were to describe the spatiotemporal patterns and epidemiology of human and livestock anthrax in the province and compare livestock vaccine coverage with human and livestock anthrax incidence. Annual incidence rates (per 10,000) for humans, buffalo/cattle, and goats were used to explore anthrax patterns and for comparison with livestock annual vaccine variations. A data subset describes anthrax epidemiology in humans by gender, age, source of infection, type of anthrax, admission site, and season. Zonal statistics and SaTScan were used to identify spatial and space-time clusters of human anthrax. SaTScan revealed space-time clusters in 1999, 2004, and 2007-2008 in the province, including in the northeastern, eastern, and western areas. Most human anthrax was reported between July and October. Most patients were male, aged 15-59 years, who had handled sick animals and/or consumed contaminated meat. High case-fatality rates were reported with gastrointestinal or respiratory cases. Our data suggest that vaccination in buffalo and cattle reduces the disease burden in humans and vaccinated animals but does not reduce the incidence in unvaccinated animals (goats). This study identified spatial areas of high risk for anthrax and can inform One Health surveillance and livestock vaccination planning in contextual settings similar to Ha Giang province.

Impact of COVID-19 on foodborne illness in Africa - A perspective piece

Food safety investments in Africa, through international donors or national programs, were primarily focused on the formal market sector. However, increasing consumer food safety concerns about foods sold in the growing informal food markets, the rising foodborne disease burden in Africa, and the emergence of COVID-19 have all made food safety a major concern and ultimately brought it to an inflection point in Africa. In addition, Data on foodborne disease outbreaks revealed a scarcity of reported cases before and during the pandemic. The lack of information on foodborne disease reporting in Africa translates into one of the reasons why food safety in Africa is becoming a rising subject matter. This perspective discusses the situation of food safety in Africa before and after the COVID-19 pandemic. Finally, challenges confronting ongoing efforts to improve food safety in the post-COVID era in Africa are summarized and highlighted.

Spatial analysis of human and livestock anthrax in Dien Bien province, Vietnam (2010-2019) and the significance of anthrax vaccination in livestock

Anthrax is a serious zoonosis caused by Bacillus anthracis, which primarily affects wild herbivorous animals with spillover into humans. The disease occurs nearly worldwide but is poorly reported in Southeast Asian countries. In Vietnam, anthrax is underreported, and little is known about its temporal and spatial distributions. This paper examines the spatio-temporal distribution and epidemiological characteristics of human and livestock anthrax from Dien Bien province, Vietnam from 2010 to 2019. We also aim to define the role of livestock vaccination in reducing human cases. Historical anthrax data were collected by local human and animal health sectors in the province. Spatial rate smoothing and spatial clustering analysis, using Local Moran's I in GeoDa and space-time scan statistic in SaTScan, were employed to address these objectives. We found temporal and spatial overlap of anthrax incidence in humans and livestock with hotspots of human anthrax in the east. We identified three significant space-time clusters of human anthrax persisting from 2010 to 2014 in the east and southeast, each with high relative risk. Most of the human cases were male (69%), aged 15-59 years (80%), involved in processing, slaughtering, or eating meat of sick or dead livestock (96.9%) but environmental and unknown exposure were reported. Animal reports were limited compared to humans and at coarser spatial scale, but in areas with human case clusters. In years when livestock vaccination was high (>~25%), human incidence was reduced, with the opposite effect when vaccine rates dropped. This indicates livestock vaccination campaigns reduce anthrax burden in both humans and livestock in Vietnam, though livestock surveillance needs immediate improvement. These findings suggest further investigation and measures to strengthen the surveillance of human and animal anthrax for other provinces of Vietnam, as well as in other countries with similar disease context.

Improving the effectiveness of Field Epidemiology Training Programs: characteristics that facilitated effective response to the COVID-19 pandemic in Uganda

BACKGROUND

The global need for well-trained field epidemiologists has been underscored in the last decade in multiple pandemics, the most recent being COVID-19. Field Epidemiology Training Programs (FETPs) are in-service training programs that improve country capacities to respond to public health emergencies across different levels of the health system. Best practices for FETP implementation have been described previously. The Uganda Public Health Fellowship Program (PHFP), or Advanced-FETP in Uganda, is a two-year fellowship in field epidemiology funded by the U.S. Centers for Disease Control and situated in the Uganda National Institute of Public Health (UNIPH). We describe how specific attributes of the Uganda PHFP that are aligned with best practices enabled substantial contributions to the COVID-19 response in Uganda.

METHODS

We describe the PHFP in Uganda and review examples of how specific program characteristics facilitate integration with Ministry of Health needs and foster a strong response, using COVID-19 pandemic response activities as examples. We describe PHFP activities and outputs before and during the COVID-19 response and offer expert opinions about the impact of the program set-up on these outputs.

RESULTS

Unlike nearly all other Advanced FETPs in Africa, PHFP is delinked from an academic degree-granting program and enrolls only post-Master's-degree fellows. This enables full-time, uninterrupted commitment of academically-trained fellows to public health response. Uganda's PHFP has strong partner support in country, sufficient technical support from program staff, Ministry of Health (MoH), CDC, and partners, and full-time dedicated directorship from a well-respected MoH staff member. The PHFP is physically co-located inside the UNIPH with the emergency operations center (EOC), which provides a direct path for health alerts to be investigated by fellows. It has recognized value within the MoH, which integrates graduates into key MoH and partner positions. During February 2020-September 2021, PHFP fellows and graduates completed 67 major COVID-related projects. PHFP activities during the COVID-19 response were specifically requested by the MoH or by partners, or generated de novo by the program, and were supervised by all partners.

CONCLUSION

Specific attributes of the PHFP enable effective service to the Ministry of Health in Uganda. Among the most important is the enrollment of post-graduate fellows, which leads to a high level of utilization of the program fellows by the Ministry of Health to fulfill real-time needs. Strong leadership and sufficient technical support permitted meaningful program outputs during COVID-19 pandemic response. Ensuring the inclusion of similar characteristics when implementing FETPs elsewhere may allow them to achieve a high level of impact.

Anthrax outbreak investigation in Tengwe, Mashonaland West Province, Zimbabwe, 2022

BACKGROUND

Anthrax continues to be a disease of public health concern in Zimbabwe. Between December 2021 and February 2022, Tengwe reported 36 cases of human anthrax. Gastrointestinal anthrax has the potential to cause serious outbreaks leading to loss of human life. We investigated the outbreak, identified the risk factors using one health approach to inform outbreak control.

MATERIALS AND METHODS

We conducted descriptive analysis of the outbreak and a 1:2 unmatched case control study to identify risk factors for anthrax. A case was any Tengwe resident who developed an ulcer and/or abdominal symptoms and epidemiologically linked to a confirmed environmental exposure. Validated, structured interviewer-administered questionnaires were used to collect data from the cases and neighbourhood controls. Soil and dried meat samples were collected for laboratory investigations. District preparedness and response was assessed using a checklist. Data was analysed using Epi Info version 7.2.5. The odds of exposure were calculated for each risk factor examined. Multivariable logistic regression analysis was performed to identify the independent factors associated with contracting anthrax.

RESULTS

Through active case finding we identified 36 cases, 31 were interviewed. Twenty-one (67.7%) were males. The median age was 33 years (Inter quartile range: 22-54). Nineteen (61.2%) cases presented with abdominal symptoms with zero deaths reported. The independent risk factor for contracting anthrax was eating under-cooked meat (aOR = 12.2, 95% CI: 1.41-105.74, p = 0.023). All samples collected tested positive for anthrax. No livestock vaccinations or zoonotic meetings were being conducted prior to the outbreak. Notification of the outbreak was done 11 days after index case presentation however one health response was instituted within 24 hours.

CONCLUSION

The anthrax was confirmed in Tengwe. Consumption of under-cooked meat was associated with gastrointestinal anthrax. The timely one health response resulted in excellent outcomes. Using one health approach in managing zoonotic threats is encouraged.

Establishing a Public Health Emergency Operations Center in an Outbreak-Prone Country: Lessons Learned in Uganda, January 2014 to December 2021

Uganda is highly vulnerable to public health emergencies (PHEs) due to its geographic location next to the Congo Basin epidemic hot spot, placement within multiple epidemic belts, high population growth rates, and refugee influx. In view of this, Uganda's Ministry of Health established the Public Health Emergency Operations Center (PHEOC) in September 2013, as a central coordination unit for all PHEs in the country. Uganda followed the World Health Organization's framework to establish the PHEOC, including establishing a steering committee, acquiring legal authority, developing emergency response plans, and developing a concept of operations. The same framework governs the PHEOC's daily activities. Between January 2014 and December 2021, Uganda's PHEOC coordinated response to 271 PHEs, hosted 207 emergency coordination meetings, trained all core staff in public health emergency management principles, participated in 21 simulation exercises, coordinated Uganda's Global Health Security Agenda activities, established 6 subnational PHEOCs, and strengthened the capacity of 7 countries in public health emergency management. In this article, we discuss the following lessons learned: PHEOCs are key in PHE coordination and thus mitigate the associated adverse impacts; although the functions of a PHEOC may be legalized by the existence of a National Institute of Public Health, their establishment may precede formally securing the legal framework; staff may learn public health emergency management principles on the job; involvement of leaders and health partners is crucial to the success of a public health emergency management program; subnational PHEOCs are resourceful in mounting regional responses to PHEs; and service on the PHE Strategic Committee may be voluntary.

Outbreak of cutaneous anthrax associated with handling meat of dead cows in Southwestern Uganda, May 2018

Background

Anthrax is a zoonotic infection caused by the bacteria Bacillus anthracis. Humans acquire cutaneous infection through contact with infected animals or animal products. On May 6, 2018, three cows suddenly died on a farm in Kiruhura District. Shortly afterwards, a sub-county chief in Kiruhura District received reports of humans with suspected cutaneous anthrax in the same district. The patients had reportedly participated in the butchery and consumption of meat from the dead cows. We investigated to determine the magnitude of the outbreak, identify exposures associated with illness, and suggest evidence-based control measures.

Methods

We conducted a retrospective cohort study among persons whose households received any of the cow meat. We defined a suspected human cutaneous anthrax case as new skin lesions (e.g., papule, vesicle, or eschar) in a resident of Kiruhura District from 1 to 26 May 2018. A confirmed case was a suspected case with a lesion testing positive for B. anthracis by polymerase chain reaction (PCR). We identified cases through medical record review at Engari Health Centre and active case finding in the community.

Results

Of the 95 persons in the cohort, 22 were case-patients (2 confirmed and 20 suspected, 0 fatal cases) and 73 were non-case household members. The epidemic curve indicated multiple point-source exposures starting on May 6, when the dead cows were butchered. Among households receiving cow meat, participating in slaughtering (RR = 5.3, 95% CI 3.2–8.3), skinning (RR = 4.7, 95% CI = 3.1–7.0), cleaning waste (RR = 4.5, 95% CI = 3.1–6.6), and carrying meat (RR = 3.9, 95% CI = 2.2–7.1) increased the risk of infection.

Conclusions

This cutaneous anthrax outbreak was caused by handling infected animal carcasses. We suggested to the Ministry of Agriculture, Animal Industry and Fisheries to strengthen surveillance for possible veterinary anthrax and ensure that communities do not consume carcasses of livestock that died suddenly. We also suggested that the Ministry of Health equip health facilities with first-line antibiotics for community members during outbreaks.

'We dry contaminated meat to make it safe': An assessment of knowledge, attitude and practices on anthrax during an outbreak, Kisumu, Kenya, 2019

Introduction

Anthrax is the highest-ranked priority zoonotic disease in Kenya with about ten human cases annually. Anthrax outbreak was reported in Kisumu East Sub County after some villagers slaughtered and ate beef from a cow suspected to have died of anthrax. We aimed at establishing the magnitude of the outbreak, described associated factors, and assessed community knowledge, attitude, and practices on anthrax.

Methods

We reviewed human and animal records, conducted case search and contact tracing using standard case definitions in the period from July 1through to July 28, 2019. A cross-sectional study was conducted to assess community knowledge, attitude, and practices towards anthrax. The household selection was done using multistage sampling. We cleaned and analyzed data in Ms. Excel and Epi Info. Descriptive statistics were carried out for continuous and categorical variables while analytical statistics for the association between dependent and independent variables were calculated.

Results

Out of 53 persons exposed through consumption or contact with suspicious beef, 23 cases (confirmed: 1, probable: 4, suspected: 18) were reviewed. The proportion of females was 52.17% (12/23), median age 13.5 years and range 45 years. The attack rate was 43.4% (23/53) and the case fatality rate was 4.35% (1/23). Knowledge level, determined by dividing those considered to be ‘having good knowledge’ on anthrax (numerator) by the total number of respondents (denominator) in the population regarding cause, transmission, symptoms and prevention was 51% for human anthrax and 52% for animal anthrax. Having good knowledge on anthrax was associated with rural residence [OR = 5.5 (95% CI 2.1–14.4; p<0.001)], having seen a case of anthrax [OR = 6.2 (95% CI 2.8–14.2; p<0.001)] and among those who present cattle for vaccination [OR = 2.6 (95% CI 1.2–5.6; p = 0.02)]. About 23.2% (26/112) would slaughter and sell beef to neighbors while 63.4% (71/112) would bury or burn the carcass. Nearly 93.8% (105/112) believed vaccination prevents anthrax. However, 5.4% (62/112) present livestock for vaccination.

Conclusion

Most anthrax exposures were through meat consumption. Poor knowledge of the disease might hamper prevention and control efforts.

Analysis of Food Safety Management Systems in the Beef Meat Processing and Distribution Chain in Uganda

Meat production is an essential component in food security and the economy in Uganda. However, food safety concerns pose a challenge to public health in Uganda and impede access to regional and global markets. Here, food safety management (FSM) practices in the Ugandan beef supply chain were evaluated. A cross-sectional survey was conducted in major slaughterhouses (n = 3), butcher shops (n = 184), and supermarkets (n = 25) in Uganda’s capital, Kampala. The three slaughterhouses had low scores in core control and assurance activities of FSM. Packaging interventions were weak in all the slaughterhouses, while only one slaughterhouse had a functional cooling facility. Supermarkets implemented better hygienic and preventative practices in comparison to butcher shops. However, both sourced from slaughterhouses that had low-to-poor hygiene practices, which weakened the efforts implemented in the supermarkets. Furthermore, most butcher shops did not offer training to meat handlers on HACCP (Hazard Analysis and Critical Control Point)-based practices. The low food safety performance in the supply chain was primarily attributed to poor sanitation, hygiene, and handling practices. Therefore, HACCP-based training and robust preventive, intervention, and monitoring systems are needed in the Ugandan beef supply chain to benefit public health and increase competitiveness.

A Review of Arguments for the Existence of Latent Infections of Bacillus anthracis, and Research Needed to Understand their Role in the Outbreaks of Anthrax

Hugh-Jones and Blackburn and Turnbull’s collective World Health Organization (WHO) report did literature reviews of the theories and the bases for causes of anthrax outbreaks. Both comment on an often-mentioned suspicion that, even though unproven, latent infections are likely involved. Hugh-Jones suggested Gainer do an updated review of our present-day knowledge of latent infections, which was the basis for Gainer’s talk at the Biology of Anthrax Conference in Bari, Italy 2019. At the Conference Gainer met Vergnaud who presented anthrax genome studies that implied that the disease might have spread throughout Asia and from Europe to North America in a short time span of three or four centuries. Vergnaud wondered if latent infections might have played a role in the process. Several other presenters at the Conference also mentioned results that might suggest the existence of latent infections. Vergnaud subsequently looked into some of the old French literature about related observations, results, and discussions of early Pasteur vaccine usage (late 1800′s) and found mentions of suspected latent infections. The first part of the paper is a focused summary and interpretation of Hugh-Jones and Blackburn’s and Turnbull’s reviews specifically looking for suggestions of latent infections, a few additional studies with slightly different approaches, and several mentions made of presentations and posters at the Conference in Italy. In general, many different investigators in different areas and aspects of the anthrax study at the Conference found reasons to suspect the existence of latent infections. The authors conclude that the affected species most studied, including Homo sapiens, provide circumstantial evidence of latent infections and modified host resistance. The last part of the review explores the research needed to prove or disprove the existence of latent infections.