5 research outputs found
Prevalence and risk behaviours of camel brucellosis transmission in the peri-urban dairy basin of Niamey, Niger
No full textConsidered as one of the most widespread zoonoses in the world and dangerous for human and animal health, brucellosis has been studied mainly in cattle and small ruminants but rarely in camels. The lack of data in Niger on this pathology in camels has aroused particular interest given the breeding method and the dietary habits of urban and peri-urban consumers. It is in this context that we conducted the first cross-sectional study on camel brucellosis in Niger, in the peri-urban dairy basin of Niamey. The general objective of this study was to determine the prevalence of camel brucellosis and the risk behaviours for its transmission at the animal-human interface. Thus, 275 serum samples and 75 camel milk samples were collected from 20 farms in 11 peri-urban localities of Niamey. The serum samples were analysed by 2 methods, namely the Rose Bengal test and indirect ELISA. The overall seroprevalence obtained with the serum samples was 4%. All 75 milk samples tested by indirect ELISA were negative. In addition, 30 camel farmers were surveyed to assess their knowledge, attitudes, and practices regarding brucellosis. The survey revealed that 96.7% of the farmers were not aware of brucellosis, the species affected and the modes of transmission. Most of participants stated that camels were in frequent contact with sheep, goats, cattle, and other species. In case of abortion, the placenta and runt are handled with bare hands and sometimes buried or thrown away. All respondents consumed raw camel milk and stated that the milk sold is not pasteurised. These elements constitute risk behaviours for the transmission of this zoonosis and urgent measures should be taken. However, epidemiological investigations must be carried out continuously in order to monitor the evolution of this major zoonosis and to establish an adapted prophylaxis that takes into account this species, in order to protect the herd but also public health.
Keywords: Camel brucellosis, seroprevalence, lacto-prevalence, KAP study, Niamey-Niger
Serological Prevalence of Contagious Bovine Pleuropneumonia in Niger in 2017
No full textContagious bovine pleuropneumonia (CBPP) is a highly contagious disease of cattle caused by Mycoplasma mycoides subsp. mycoides Biotype Small Colony (MmmSC). The disease currently occurs in most of sub-Saharan Africa and where it is endemic and a major constraint for improving pastoral productivity. Following the persistence of this scourge, and in order to control this disease, a serological survey was conducted to determine the prevalence of CBPP in Niger. In fact, 1,590 sera were collected following a stratified sampling plan based on the risk factor of dissemination of CBPP. The analysis were performed at the Central Livestock Laboratory using the c-Elisa test. The results obtained show a wide distribution of the disease with an overall prevalence of 4.15% at individual level. The highest prevalences were recorded in the South-East regions [Zinder (7.5%), Diffa (7.5%)] and the West part [Tahoua (6.9%)]. The prevalence at the commune level was about 36.55%, which was relatively high. The prevalence at strata level was 36.55% (95% PI 0.2428–0.4882). The expected prevalences did not match those found. The results of this serological survey are considered the reference situation (T0) of CBPP in Niger with the PRAPS project, and allowed to the country to redefine control policies for better control of the disease at national and sub-regional level
Seroprevalence of Rift Valley Fever Viruses Antibodies in Domestic Livestock in the Tahoua Region of Niger
No full textRift Valley Fever (RVF) remains a significant public health and economic concern in Niger, particularly in the Tahoua region. This study aimed to update seroprevalence estimates of Rift Valley Fever Virus (RVFV) and identify high-risk areas and animal populations. A cross-sectional survey was conducted between January and May 2024, during which 615 domestic ruminants (cattle, sheep, goats, and camels) were sampled and tested for RVFV-specific antibodies using a competitive enzyme-linked immunosorbent assay (cELISA).
The overall RVFV seroprevalence in the Tahoua region was 11.87% (±2.55%). Camels exhibited the highest seroprevalence (36.56%), followed by cattle (17.69%), while small ruminants showed much lower rates: 3.55% in goats and 3.37% in sheep. Significant geographic heterogeneity was observed, with the highest prevalence recorded in Birni N'Konni (30.53%, p < 0.05). No statistically significant differences in seroprevalence were found by sex (p = 0.909) or age (p = 0.876), although adults and females tended to have slightly higher rates.
These findings confirm ongoing RVFV circulation in the region and identify camels as the most affected species. The results underscore the need for enhanced, species-specific surveillance, targeted vaccination campaigns, and vector control strategies in high-risk areas to prevent future outbreaks and protect both animal and human health
Brucellosis in dairy herds: a public health concern in the milk supply chains of West and Central Africa
No full textTen herd-level cross-sectional studies were conducted in peri-urban dairy production areas of seven West and Central African countries (Burkina Faso, Burundi, Cameroon, Mali, Niger, Senegal and Togo). The objectives were to estimate herd level Brucella spp. seroprevalence and identify risk factors for seropositivity.
In each of the ten study areas, herds (between 52 and 142 per area, total = 965) were selected probabilistically and a structured questionnaire was administered to gather information on their structure and management. A bulk milk sample from each herd was tested by indirect ELISA for Brucella spp. For each area, herd seroprevalence estimates were obtained after adjusting for the assumed performance of the diagnostic test. Herd level risk factors for Brucella spp. seropositivity were identified by means of stratified logistic regression, with each peri-urban zone as a stratum. Area-specific models were also explored.
Estimated herd seroprevalences were: Lomé (Togo) 62.0% (95% CI:55.0-69.0), Bamako (Mali) 32.5% (95% CI:28.0-37.0), Bujumbura (Burundi) 14.7% (95%CI:9.4-20.8), Bamenda (Cameroon) 12.6% (95% CI:7.6-21.9), Ouagadougou (Burkina Faso) 3.0% (95% CI:1.0-9.1), Ngaoundere (Cameroon) 2.3% (95% CI:1.0-7.0), Thies (Senegal) 1.3% (95% CI:0.1, 5.3), Niamey (Niger) 1.2% (95% CI:0.08-5.3), Dakar (Senegal) 0.2% (95% CI:0.01-1.7) and Niakhar (Senegal) <0.04%. Logistic regression modelling revealed transhumant herds to be at lower risk of infection (adjusted OR: 0.25, 95% CI: 0.13 - 0.5) and in one of the areas (Bamenda), regular purchase of new animals was found to be strongly associated with Brucella spp. seropositivity (adjusted OR = 5.3, 95% CI: 1.4-25.9). Our findings confirm that Brucella spp. circulates among dairy cattle supplying milk to urban consumers in West and Central Africa, posing a serious public health concern. Control programs are urgently needed in areas such as Lomé or Bamako, where more than 30% of the herds show evidence of infection
External quality assessment of Rift Valley fever diagnosis in countries at risk of the disease: African, Indian Ocean and Middle-East regions
No full textInternational audienceRift Valley fever virus (RVFV), an arbovirus belonging to the Phlebovirus genus of the Phenuiviridae family, causes the zoonotic and mosquito-borne RVF. The virus, which primarily affects livestock (ruminants and camels) and humans, is at the origin of recent major outbreaks across the African continent (Mauritania, Libya, Sudan), and in the South-Western Indian Ocean (SWIO) islands (Mayotte). In order to be better prepared for upcoming outbreaks, to predict its introduction in RVFV unscathed countries, and to run efficient surveillance programmes, the priority is harmonising and improving the diagnostic capacity of endemic countries and/or countries considered to be at risk of RVF. A serological inter-laboratory proficiency test (PT) was implemented to assess the capacity of veterinary laboratories to detect antibodies against RVFV. A total of 18 laboratories in 13 countries in the Middle East, North Africa, South Africa, and the Indian Ocean participated in the initiative. Two commercial kits and two in-house serological assays for the detection of RVFV specific IgG antibodies were tested. Sixteen of the 18 participating laboratories (88.9%) used commercial kits, the analytical performance of test sensitivity and specificity based on the seroneutralisation test considered as the reference was 100%. The results obtained by the laboratories which used the in-house assay were correct in only one of the two criteria (either sensitivity or specificity). In conclusion, most of the laboratories performed well in detecting RVFV specific IgG antibodies and can therefore be considered to be prepared. Three laboratories in three countries need to improve their detection capacities. Our study demonstrates the importance of conducting regular proficiency tests to evaluate the level of preparedness of countries and of building a network of competent laboratories in terms of laboratory diagnosis to better face future emerging diseases in emergency conditions
