A serological survey of anthrax in domestic dogs in Zimbabwe: a potential tool for anthrax surveillance.

Anthrax is an important disease caused by the bacterium Bacillus anthracis affecting both domestic and wild animals at the wildlife/livestock interface, defined here as a physical space in which wild and domestic species overlap in range and potentially interact. In endemic regions, sporadic anthrax outbreaks occur, causing significant deaths of both wildlife and livestock and sporadically, humans. However, it may also occur as isolated outbreaks with a few animals affected. Such isolated anthrax outbreaks maybe missed. High seroprevalence among carnivores suggests either regular non-fatal exposure to the pathogen circulating in a given environment, or contact with missed cases through consumption of anthrax carcases. To investigate the relevance of this potential indicator, a cross-sectional study was conducted to determine anthrax seroprevalence in domestic dogs (Canis lupus familiaris) from selected interface and non-interface areas of Zimbabwe with known history of anthrax outbreaks. Based on past anthrax outbreaks in the respective areas, the sites were further classified as high or low risk areas for anthrax outbreaks. Sera were collected from domestic dogs (n = 186) and tested for antibodies against B. anthracis protective antigens (PA) using an ELISA test. The overall seroprevalence was 51.6% (96/186; 95% CI 44.2-59.0). Sites from the non-interface areas recorded a significantly (P < 0.001) higher (72.1%) anthrax seroprevalence compared with those from the wildlife -livestock interface (41.5%). The results demonstrated a strong association (χ2 = 14.3; OR = 3.2, 1.6 < OR < 6.2, P < 0.001) between anthrax seropositivity and interface type. Low-risk sites (42.5%) had a significantly (P = 0.044) lower seroprevalence compared with high-risk sites (58.5%) but still demonstrated high seroprevalence for areas where anthrax was last reported more than 20 years back. Dogs from Tsholotsho South were more than 90-times (OR = 96.5, 13.5 < OR < 690.8) more likely to be seropositive compared with those from Hwange. The study demonstrated the potential to use domestic dogs as indicators of anthrax in the study areas to survey anthrax circulation in supposed low-risk areas and calls for a redefinition of both low and high risk areas for anthrax in Zimbabwe based on an improved surveillance.

The prevalence of red-cell antigens and antibodies in Malawi.

As there were no reliable data in Malawi for the prevalence of red cell alloantibodies or antigens in the population, a study was conducted to screen 1000 patients for the presence of antibodies and to type them for ABO, RhD, C, c, E, e and K antigens and to test 500 donors for these antigens plus Fy(a), Fy(b), Jk(a), Jk(b), S and s. Red cell antibodies were identified in 11 patients [1.1%]; 2 were anti-D, 2 anti-S, 1 anti-Le(a+b) and 6 anti-M, 4 of which were found in non-transfused males suggesting they might be naturally acquired. The antigen frequencies found were similar to those previously published for Central Africa but 98.2% of donors were found to be Fy(a-b-). All patients tested were K negative and only three donors were found to be K positive, one being a Caucasian. Approximately 3.5% of Malawians are D negative, lower than the usual 8% quoted for Black Africans. These data confirm the assumption that pre-transfusion antibody screening is not currently required but that use of the indirect antiglobulin test in the cross-match is necessary. Haemolytic disease of the newborn (HDN) appears to be rare, or under reported, in Malawi, and more work is needed to find the real incidence of this condition.

Tick infestation, and udder and teat damage in selected cattle herds of Matabeleland South, Zimbabwe.

A cross-sectional survey was conducted to determine tick infestation, and udder and teat damage in 286 lactating cows and heifers at six properties in the smallholder and commercial sectors in Gwanda district of Matabeleland South Province, Zimbabwe. Eight tick species were identified: Amblyomma hebraeum, Hyalomma truncatum, Hyalomma marginatum rufipes, Rhipicephalus evertsi evertsi, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus appendiculatus, Rhipicephalus zambeziensis and Rhipicephalus simus. Overall, 81.5% of the cattle were tick infested; prevalence of tick-infested cattle was significantly higher on communal land (93.8%) and recently claimed land (85.1%) than on commercial farms. The mean tick load on infested cattle on communal land was significantly higher than in the other two sectors. Although 53% of the sampled cattle had some degree of udder and teat damage, very few farmers (2.6%) treated their cattle for these conditions. Udder damage was ca. two times and three times, respectively, more likely to occur in cattle on communal land compared to cattle on recently claimed land and commercial farms. The occurrence of R. appendiculatus and R. zambeziensis indicate that the cattle population in the study area is at high risk of a theileriosis outbreak, a tick-borne disease that has not been reported from this area.

[Surgical masks--effective protection against cytostatic aerosols?]. / Operationsmasken--wirksamer Schutz gegen Zytostatika-Aerosole?

A surgical mask, a coarse-dust mask and five types of fine-dust masks were tested by enhanced light microscopy and cross-sectional thickness measurements for their effectiveness against inhalation of cytostatic aerosols. The construction of surgical masks most nearly resembles that of coarse-dust masks with respect to quality and number of layers. They are thus not suitable as protection against inhalation of cytostatic aerosols. Such masks must be at least particle-filtering half-masks of type DIN 58645 FHM - P2 (fine-dust masks of protective stage P2).