A Study on the Knowledge, Awareness, Perceptions and Behaviour (KAPB) of Students of the University of the West Indies, St. Augustine (UWI-STA) Towards Climate Change and its Impact on Human Health

Climate change (CC) is defined as long-term weather changes in the Earth's climate. CC has been linked to increased global temperatures. This affects human health both directly and indirectly: Directly, via increased risk of cardiovascular, respiratory, and vector-borne diseases. Indirectly, via reduced agricultural crop yields and accessibility to healthcare due to extreme weather events. Studies show that spreading awareness on the health impacts of CC encourages motivation towards mitigation (1). Early awareness of climate change and its health impacts is necessary for future generations to mitigate its effects.

Prevalence and Genetic Diversity of Toxoplasma gondii in Free-Ranging Chickens from the Caribbean.

PURPOSE: Toxoplasma gondii is a zoonotic parasite capable of infecting a wide range of hosts. Free-range chickens are important sentinels in the epidemiology of this parasite as they feed from the ground and are likely to ingest oocysts shed in the faeces of infected cats. Atypical strains of T. gondii are known to dominate in South America where they are associated with more severe disease in humans, yet relatively little is known about the strains circulating in neighbouring Caribbean islands. METHODS: In this study, hearts and brains were collected from free-range chickens in Antigua and Barbuda (n = 45), Dominica (n = 76) and Trinidad (n = 41), and DNA was extracted for nested ITS1 PCR and PCR-RFLP. Sera were collected and screened for antibodies using the modified agglutination test (MAT). RESULTS: Antibodies to T. gondii were detected in 20.5, 38.2 and 17.1% of chickens in Antigua and Barbuda, Dominica and Trinidad, respectively. Toxoplasma gondii DNA was also detected by PCR in 24.4, 17.1 and 17.1% of chickens, respectively, giving an overall prevalence of 31.1, 42.1, and 29.3% for each of the 3 island nations. Results of PCR-RFLP revealed 2 new atypical genotypes (designated ToxoDB #281 and #282) and one Type III (ToxoDB #2) in chickens from Antigua. Partial genotyping of a further 8 isolates (7 from Antigua and one from Trinidad) revealed different allele-types at five or more markers for 7 of the isolates, suggesting atypical genotypes. CONCLUSIONS: This is the first study to report the prevalence of T. gondii in free-range chickens in Antigua and Barbuda, Dominica and Trinidad and Tobago. It is also the first to report the presence of atypical genotypes in Antigua and Barbuda and Trinidad and Tobago.

The identification and characterization of high impact avian viruses circulating in wild and domestic birds in Trinidad and Tobago

Objective: To identify the extent of circulation and specific characteristics of various high priority avian viruses in wild and domestic birds in Trinidad and Tobago (T&T). Viruses included Avian Influenza virus (AIV), Infectious bronchitis virus (IBV), Newcastle disease virus (NDV), Infectious laryngotracheitis virus (ILTV) Avian metapneumovirus (aMPV), Infectious bursal disease virus (IBDV), Chicken infectious anaemia virus (CIAV), Fowl adenovirus Gp1 (FADV) and Egg drop syndrome virus (EDSV). Design and Methodology: A combination of active and passive surveillance of wild and domestic birds was carried out. Samples were tested for antibodies by enzymelinked immunosorbent assay (ELISA) and for virus by polymerase chain reaction (PCR) / sequencing to identify and characterise the circulating viruses and to determine their serotype and genotype. Results: Antibodies were detected against IBV, NDV, ILTV, APV, IBDV, FADV and EDSV and viral nucleic acid was detected for IBV, APV, CIAV and FADV in domestic poultry in T&T. Further characterisation of FADV revealed that serotypes 8a, 8b, 9, and 11 were circulating in diseased birds, along with CIAV. Phylogenetic analysis of circulating IBV strains identified two lineages, one with high similarity to the vaccine strains and the second being identified as a unique lineage to T&T. AIV antibodies with high neutralising titres against a low pathogenic H5N3 strain were detected in sera from three wild birds, and AIV RNA was detected by PCR in a swab sample taken from another wild bird. Conclusions: This research identified for the first time the presence of various high-impact avian viruses in domestic poultry and wild birds in T&T.

Identifying novel Mycobacterium species in fish using multiple gene phylogenetic analysis

Mycobacteria have, for a long time, been suspected to be causing severe disease in ornamental and farmed fish in Trinidad and Tobago (T&T), however, up to now, these mycobacteria species have not been identified and characterised. Many piscine mycobacteria species are also known to be zoonotic, potentially affecting human health. Objective: To identify and characterize the species of mycobacteria affecting fish (and possibly man) in T&T. Design and Methodology: Homogenised internal organs were collected from a total of 13 fish showing clinical signs consistent with mycobacterial infection. Samples were analysed using Ziehl-Neelsen (acid-fast) staining and real-time Polymerase Chain Reaction (rPCR). The species of mycobacteria were further characterised using conventional PCR targeting the 16s rRNA (564 bp), rpoB (396 bp) and sod (408 bp) genes. PCR products were sequenced and the sequences were compared with those from known and recently identified mycobacteria species through phylogenetic analysis. Results: Acid-fast non-branching bacilli were detected in all samples. All samples were also positive for Mycobacterium sp. by real-time PCR. Multi-gene phylogenetic analysis revealed the presence of two distinct species of mycobacteria. One aligned closely with Mycobacterium marinum, a well known pathogen affecting fish and man, and a second aligned closely with a species also known to affect both fish and humans, Mycobacterium stomatepiae. Conclusions: Phylogenetic analysis demonstrated the presence of two mycobacterium species in organs from fish showing clinical signs of Piscine Mycobacteriosis in T&T. Further work is needed to characterise these mycobacteria species and investigate their zoonotic potential.

Bluetongue virus infection in naïve cattle: Identification of circulating serotypes and associated Culicoides biting midge species in Trinidad.

To better understand risks associated with trading cattle, it is important to know which serotypes of Bluetongue virus (BTV) are circulating within the exporting and importing country. Hence, this study was conducted to identify the circulating serotypes of BTV in Trinidad. Blood samples were collected monthly from sixty BTV- naïve imported cattle over a six month period after their arrival in the country. Virological (PCR and virus isolation) and serological (ELISA) analyses were carried out on the samples and CDC light traps were placed near the cattle enclosure to trap and identify the species of Culicoides biting midges that were present. All of the cattle seroconverted for BTV antibodies within three months of their arrival in the country and real-time reverse transcription PCR (rRT-PCR) detected BTV-RNA in the samples throughout the remainder of the study. The patterns of infection observed in the cattle indicated serial infections with multiple serotypes. A combination of BTV serotype-specific rRT-PCR on the original blood samples and virus isolation followed by serotype-specific rRT-PCR on selected samples, confirmed the presence of BTV serotypes 1, 2, 3, 5, 12 and 17. This is the first report of BTV-2 and BTV-5 in Trinidad. Light-suction traps placed in close proximity to the cattle predominantly trapped Culicoides insignis Lutz 1913 species (96%), with a further six Culicoides species making up the remaining 4% of trapped samples. The circulation of multiple BTV serotypes in Trinidad underlines the need for regular surveillance, which will contribute to the development of risk assessments for trade in livestock.

Comparison of UV light-suction, incandescent light-suction, semiochemical /CO2-baited and sweepnet traps considering the Culicoides specimen yield, species diversity and crepuscular activity in South Oropouche, Trinidad, W I

Current Culicoides biting midge trapping studies in Trinidad, West Indies, using miniature CDC lightsuction traps have been yielding relatively low numbers of specimens and different species when compared to studies done over 20 years ago that primarily used similar incandescent light-suction traps (Mo et al., 1994). To determine whether this new data is a fair representation of the current status of midges in Trinidad, we compared three different trap types (UV light-suction, incandescent light-suction and 1- Octen-3-ol/CO2-baited), placed in three different set positions (3x3 randomized Latin square design) in a small dairy goat farm located in South Oropouche, Siparia, Trinidad. In a separate exercise at the same farm, we also investigated whether certain Culicoides species showed peak activity in the earlier evening (diurnal species) or later evening (nocturnal species). The farm was sweep-net every 15 minutes for the last two hours of daylight over four days. For both exercises, midges were sorted out and placed in 70% ethanol until speciated via morphology using established biological keys (Aitken et al., 1975). The trap-comparison exercise (total number = 30,702) indicated the semiochemical-baited and UV-light traps gave significantly better specimen yield and species diversity than the incandescent light traps; an apparent gender bias was also noted dependent on the type of trap used. The sweep-net exercise (total number = 975) indicated Culicoides species diversity was fairly constant with C. furens and C. pusillus present at all of the time intervals; however, the highest species diversity was observed between 18:00 and 18:15. Interestingly, C. aitkeni consistently appeared from 17:30 onwards.

One Health, One Caribbean, One Love ­ Caribbean Leadership, Regional Cooperation, Local Action

Inter-sectoral collaboration is extremely limited, both at policy and technical levels, across the Caribbean region. However, many of the priority health problems currently facing the region, like climate change, food security, ocean health, and emerging diseases arise from the interactions between people, animals and our shared environment. If these health issues are to be addressed effectively and efficiently, an intersectoral or One Health approach is clearly required. The European Union funded project "One Health, One Caribbean, One Love" set out to promote and entrench a "One Health" approach to priority health issues affecting humans, animals and the environment within the Caribbean region. The project, which spanned from March 2014 and ended in June 2017, successfully built the capacity of the national veterinary, public health and environmental health services, through the development of a cadre of One Health Leaders, the creation of Caribbean regional and national One Health Networks, and the development of a One Health strategic framework. The One Health Leadership Series developed a core group of One Health Leaders from 12 Caribbean countries. The leaders attended a series of 5 themed One Health Leadership workshops, and each country team developed and conducted a One Health project addressing a national priority health issue at the interface between human, animal and environmental health ­ a learning by doing approach. The One Health leadership series has enabled the leaders to more effectively design and manage One Health policies, programs and projects in order to develop more holistic scientific solutions to emerging health problems.

Safety and immunogenecity of a live attenuated Rift Valley fever vaccine (CL13T) in camels.

BACKGROUND: Rift Valley fever is an emerging zoonotic viral disease, enzootic and endemic in Africa and the Arabian Peninsula, which poses a significant threat to both human and animal health. The disease is most severe in ruminants causing abortions in pregnant animals, especially sheep animals and high mortality in young populations. High mortality rates and severe clinical manifestation have also been reported among camel populations in Africa, to attend however none of the currently available live vaccines against RVF have been tested for safety and efficacy in this species. In this study, the safety and efficacy (through a neutralizing antibody response) of the thermostable live attenuated RVF CL13T vaccine were evaluated in camels in two different preliminary experiments involving 16 camels, (that 12 camels and 4 pregnant camels). RESULTS: The study revealed that the CL13T vaccine was safe to use in camels and no abortions or teratogenic effects were observed. The single dose of the vaccine stimulated a strong and long-lasting neutralizing antibody response for up to 12 months. CONCLUSION: The presence of neutralization antibodies is likely to correlate with protection; however protection would need to be confirmed by challenge experiments using the virulent RVF virus.

African horse sickness outbreaks caused by multiple virus types in Ethiopia.

African horse sickness (AHS) is associated with high morbidity and mortality in equids, especially horses. A retrospective analysis was carried out concerning 737 AHS outbreaks that occurred during 2007-2010 in Ethiopia. A total of ten outbreaks were investigated in the study period. All four forms of the disease (pulmonary, cardiac, horse sickness fever and the combined form) were observed, with the cardiac form being the most prevalent. Multiple African horse sickness virus serotypes (AHSV-2, AHSV-4, AHSV-6, AHSV-8 and AHSV-9) were detected by molecular methods (type-specific real-time RT-PCR assays), and fourteen isolates were derived from blood and tissue samples collected during 2009-2010. This is the first report of AHSV-4, AHSV-6 or AHSV-8 in Ethiopia.

No evidence for replication of a field strain of bluetongue virus serotype 1 in the blood of domestic dogs.

The potential role of domestic dogs in the long-distance transmission of bluetongue virus (BTV) is currently unproven. This study set out, through an experimental infection study, to investigate whether domestic dogs mount a viraemia post-infection with a field strain of BTV serotype 1. All six experimentally infected dogs seroconverted within 14 days and viral RNA was detected in the blood of the dogs, albeit at significantly lower levels than that seen in domestic ruminants. There was no clear evidence for viral replication in the dogs as no increase in viral RNA was observed in, and it was not possible isolate virus from, the blood of the dogs. There was however evidence for a persistence of viral RNA in the blood of the dogs, which may be evidence for a low level of replication or could be indicative of persistence of the viral inoculum.

Evaluation of the humoral immune responses in adult cattle and sheep, 4 and 2.5 years post-vaccination with a bluetongue serotype 8 inactivated vaccine.

One of the big surprises about the devastating outbreak of bluetongue serotype-8 that spread across Northern and Western Europe between 2006 and 2008 was how relatively quickly the virus was controlled and eradicated from affected countries. This was at least in part attributed to the high levels of vaccine coverage achieved in affected countries. A previous study revealed that neutralising antibodies persisted in the majority of vaccinated cattle for at least 3 years post-vaccination, indicating that cattle are likely to be protected for this time period. The current study revealed that neutralising antibodies persisted in the same group of cattle for up to 4 years post-vaccination, and that neutralising antibodies persisted for up to 2.5 years in sheep that had been vaccinated on two occasions one year apart. These results have implications for future bluetongue surveillance programmes and vaccine control strategies.

Haemoparasite infection kinetics and the population structure of Theileria parva on a single farm in Uganda.

The development of sensitive PCR-based species-specific diagnostics and parasite genotyping methods offer the opportunity to provide important and detailed information on the infection dynamics of tick-borne disease. In this study we have exploited such tools to investigate the infection kinetics and parasite diversity within Theileria parva in a single farm in Uganda. Initial analysis of a sample of cattle showed high levels of infection with three Theileria species and Ehrlichia bovis, with most animals being infected with more than one pathogen. To study the infection dynamics, newborn calves were sampled longitudinally and it was shown that all animals became infected with T. parva, T. mutans, T. velifera and E. bovis with the average time to first infection being 53, 74, 116 and 109 days, respectively. However, the majority of these calves cleared the infections with T. parva and E. bovis but remained infected with the other two species of Theileria. In order to investigate the diversity of infecting genotypes of T. parva, samples from six calves were genotyped with a single mini-satellite marker at time points over a nine-month period. Each animal was infected with multiple different sets of genotypes and these were lost over different periods of time, implying that immunity is induced against particular infecting strains. To undertake a higher resolution analysis of parasite genotypes, samples from 30 calves were genotyped with a full panel of 12 micro- and mini-satellite markers but, due to the presence of mixed infections, only 16 samples could be used to generate parasite multi-locus genotypes (MLGs). A high degree of diversity of T. parva was seen on the farm, although some MLGs occurred more than once. Similarity analysis demonstrated a level of sub-structuring and the T. parva population was found to be in linkage disequilibrium. The basis for this high diversity coupled with apparent sub-structuring is discussed in relation to the possible causes.

Mechanical transmission of lumpy skin disease virus by Rhipicephalus appendiculatus male ticks.

Lumpy skin disease (LSD) is an economically important, acute or sub-acute, viral disease of cattle that occurs across Africa and in the Middle East. The aim of this study was to investigate if lumpy skin disease virus (LSDV) can be transmitted mechanically by African brown ear ticks (Rhipicephalus appendiculatus Neum.). Laboratory-bred R. appendiculatus males were fed on experimentally infected viraemic 'donor' cattle. Partially fed male ticks were then transferred to feed on an uninfected 'recipient' cow. The recipient animal became viraemic, showed mild clinical signs of LSD and seroconverted. Additionally, R. appendiculatus males were found to transmit LSDV through feeding on skin lacking visible lesions, demonstrating that viraemic animals without lesions at the feeding site of ticks may be a source of infection. This is the first time that transmission of poxviruses by a tick species has been demonstrated and the importance of this mode of transmission in the spread of LSDV in endemic settings is discussed.

Bluetongue virus serotype 26: infection kinetics, pathogenesis and possible contact transmission in goats.

The aim of this study was to assess the pathogenicity and infection kinetics of Bluetongue virus serotype 26 (BTV-26) in goats. Out of a group of six goats housed in insect free accommodation, five were experimentally infected with BTV-26 and one was kept uninfected as an in-contact control. Samples taken throughout the study were used to determine the kinetics of infection using a pan specific BTV real time RT-PCR assay and a group specific ELISA. The five infected goats did not show clinical signs of BTV, however high levels of viral RNA were detected and virus was isolated from the blood of all 5 goats. Antibodies against BTV were first detected between 7 and 11 dpi in all 5 experimentally infected goats. Interestingly at 21 dpi viral RNA was detected in, and virus was isolated from, the blood of the in-contact control goat, which also seroconverted. These results suggest that BTV-26 replicates to high levels in goats, causing no obvious clinical disease, suggesting that goats may be the natural host for this virus. Preliminary evidence also indicates that BTV-26 may be spread by contact transmission between goats, however a more detailed study is required in order to confirm this observation.

Bluetongue and epizootic haemorrhagic disease virus in local breeds of cattle in Kenya.

The presence of bluetongue virus (BTV) and Epizootic Haemorrhagic Disease virus (EHDV) in indigenous calves in western Kenya was investigated. Serum was analysed for BTV and EHDV antibodies. The population seroprevalences for BTV and EHDV for calves at 51 weeks of age were estimated to be 0.942 (95% CI 0.902-0.970) and 0.637 (95% CI 0.562-0.710), respectively, indicating high levels of circulating BTV and EHDV. The odds ratio of being positive for BTV if EHDV positive was estimated to be 2.57 (95% CI 1.37-4.76). When 99 calves were tested for BTV and EHDV RNA by real-time RT-PCR, 88.9% and 63.6% were positive, respectively. Comparison of the serology and real-time RT-PCR results revealed an unexpectedly large number of calves that were negative by serology but positive by real-time RT-PCR for EHDV. Eight samples positive for BTV RNA were serotyped using 24 serotype-specific real-time RT-PCR assays. Nine BTV serotypes were detected, indicating that the cattle were infected with a heterogeneous population of BTVs. The results show that BTV and EHDV are highly prevalent, with cattle being infected from an early age.

Virological diagnosis of African swine fever--comparative study of available tests.

The rapid and reliable detection of African swine fever virus (ASFV) is essential both for timely implementation of control measures to prevent the spread of disease, and to differentiate African swine fever (ASF) from other pig disease with similar clinical presentations. Many virological tests are currently available for the detection of ASFV (live virus), antigen and genome, including virus isolation, ELISA, fluorescent antibody, polymerase chain reaction (PCR) and isothermal assays. In recent years real-time PCR (rPCR) has become one of the most widely used formats for virological diagnosis providing sensitive, specific and swift detection and quantification of ASFV DNA. The ability to integrate rPCR into automated platforms increases sample throughput and decreases the potential for cross-contamination. In more recent years isothermal assays, which are a lower-cost alternative to PCR more suitable for use in non-specialised or mobile laboratories, have been developed for the detection of ASFV, however these assays have not been fully validated for routine use in the field. The performance of all virological detection assays in ASF diagnostics, as well as prospects for improving diagnostic strategies in the future, are discussed and reviewed in this chapter.

Bluetongue virus serotype 26: infection kinetics and pathogenesis in Dorset Poll sheep.

Bluetongue virus serotype 26 (BTV-26) has recently been isolated from sheep in Kuwait. The aim of this study was to assess the pathogenicity and infection kinetics of BTV-26 in Dorset Poll sheep. Six sheep were experimentally infected with BTV-26 and samples taken throughout the study were used to determine the kinetics of infection using a pan specific BTV real time RT-PCR assay and two group specific ELISAs. Five of the six sheep showed mild clinical signs characteristic of bluetongue including conjunctivitis, reddening of the mouth mucosal membranes, slight oedema of the face and nasal discharge. Viral RNA was detected in 5 of the 6 sheep by real time RT-PCR, however the levels of viral RNA detected in the samples were lower and of shorter duration than seen with other field strains of BTV. Virus was isolated from the blood of infected animals at the peak of viraemia at around 9 dpi. Antibodies against BTV were first detected by 7 dpi using the early detection BTV ELISA and a little later (7-14 dpi) using a BTV specific competitive ELISA. Four of the five remaining sheep developed neutralising antibodies to BTV-26, measured by a serum neutralisation test (SNT), with titres (log(10)) ranging from 1.40 to 2.08.

Evaluation of the humoral immune response in adult dairy cattle three years after vaccination with a bluetongue serotype 8 inactivated vaccine.

Despite the widespread use of bluetongue serotype 8 (BTV-8) inactivated vaccines across Europe from 2008 to 2011, two very practical questions remain unanswered about the length of persistence of group-specific antibodies in milk and serum post-vaccination and the duration of protection beyond one year post-vaccination. This study has firstly revealed that group-specific antibodies persist at high levels in milk and serum in the majority of cattle for at least 3 years post-vaccination, thus removing the option of using these animals in ELISA-based surveillance programmes. Secondly neutralising antibodies have been shown to persist in the majority of cattle for at least 3 years post-vaccination, indicating that the cattle are likely to be protected for this time period. This extended duration of protection may have contributed towards the rapid and efficient eradication of BTV-8 from many European countries, despite reducing levels of vaccine coverage.

First evidence of peste des petits ruminants (PPR) virus circulation in Algeria (Sahrawi territories): outbreak investigation and virus lineage identification.

Following reports of increased mortality in the small ruminant population of the Sahrawi territories, western Algeria, between January and May 2010, local veterinary authorities suspected an outbreak of peste des petits ruminants (PPR). An investigation was implemented in May 2010 and followed up in October 2010 in the Sahrawi refugee camps, Tindouf province, with the objective of confirming the circulation of the peste des petits ruminants virus (PPRV). Laboratory results confirmed the presence of PPRV in 33.3% of the samples. Sequence analysis revealed that the virus belonged to Lineage IV and phylogenetic analysis indicated a close relationship (99.3%) with the PPRV isolated during the Moroccan outbreak in 2008.

African horse sickness in The Gambia: circulation of a live-attenuated vaccine-derived strain.

African horse sickness virus serotype 9 (AHSV-9) has been known for some time to be circulating amongst equids in West Africa without causing any clinical disease in indigenous horse populations. Whether this is due to local breeds of horses being resistant to disease or whether the AHSV-9 strains circulating are avirulent is currently unknown. This study shows that the majority (96%) of horses and donkeys sampled across The Gambia were seropositive for AHS, despite most being unvaccinated and having no previous history of showing clinical signs of AHS. Most young horses (<3 years) were seropositive with neutralizing antibodies specific to AHSV-9. Eight young equids (<3 years) were positive for AHSV-9 by serotype-specific RT-PCR and live AHSV-9 was isolated from two of these horses. Sequence analysis revealed the presence of an AHSV-9 strain showing 100% identity to Seg-2 of the AHSV-9 reference strain, indicating that the virus circulating in The Gambia was highly likely to have been derived from a live-attenuated AHSV-9 vaccine strain.