Augustino Chengula

Background Tanzania has experienced periodic dengue outbreaks with increased incidence since 2010. However, there is limited information on vector dynamics and transmission risk in most parts of the country. This study was conducted to determine Aedes mosquito abundance, larval indices and dengue virus infection rate as risk indicators for DENV transmission in Kinondoni district, Dar es Salaam, Tanzania. Methods A cross-sectional study was conducted in three wards of Kinondoni district in Tanzania between December 2019 and January 2020. In each ward, three streets were randomly selected for adult and immature mosquito sampling. The adult mosquitoes were collected using Mosquito Magnet traps, while mosquito larvae and pupae were inspected in water-holding containers in the selected household compounds. The detection of dengue virus (DENV) in female Aedes mosquitoes was done using a one-step reverse transcription–polymerase chain reaction (RT–PCR) method. Results Of the 1416 adult fem...

Rift Valley fever (RVF) is a viral notifiable zoonotic disease primarily of domestic ruminants that causes significant socio-economic impacts. Using the 2006–07 outbreak cases, this study aimed to establish the socio-economic impact of RVF and assessing knowledge, attitude and practice of livestock keepers towards controlling RVF in selected areas of Tanzania. Data were collected in Arusha, Manyara and Morogoro regions using questionnaires, focus group discussions and in-depth interviews with key informants. Results indicate that there was little knowledge on disease (all clinical signs scored <50%) and the difference between the three regions was statistically significant (P = 0.00459). Socio-economic impacts of RVF shown by this study included; animal and human deaths, disruption of livestock market chains, inability of pastoralists to achieve their daily demands, inability to obtain protein leading to malnutrition and monetary loss at individual and national level during contr...

The circulation of infectious diseases in the community settings in urban and rural areas remains to be a hectic problem. One of the sources of microbial diseases is toilets. This study aimed at isolating, identifying and establishing bacterial loads associated with public restrooms in students’ hostels at Sokoine University of Agriculture in Morogoro, Tanzania. Samples were collected from a total of thirty toilets (60 samples) in different surfaces; (i) surfaces associated with toilets (toilet seats and toilet bowls), (ii) surfaces routinely touched with hands (door handles in and out of the restrooms, faucet handles and toilet flush handles) and (iii) the restroom floors. Samples were inoculated in MacConkey and Blood agar and then incubated at 37 o C for 24 hours. All isolates were sub cultured and identified based on macro- and micro-morphology and Standard Biochemical Tests. The establishment of total bacteria load was done using Standard Plate Count Method. The sensitivity tes...

Tilapia lake virus disease (TiLVD) has emerged to be an important viral disease of farmed Nile tilapia (Oreochromis niloticus) having the potential to impede expansion of aquaculture production. There is a need for rapid diagnostic tools to identify infected fish to limit the spread in individual farms. We report the first detection of TiLV infection by PCR in farmed and wild Nile tilapia from Lake Victoria. There was no difference in prevalence between farmed and wild fish samples (p = .65), and of the 442 samples examined from 191 fish, 28 were positive for TiLV by PCR. In terms of tissue distribution, the head kidney (7.69%, N = 65) and spleen (10.99%, N = 191), samples had the highest prevalence (p < .0028) followed by heart samples (3.45%, N = 29). Conversely, the prevalence was low in the liver (0.71%, N = 140) and absent in brain samples (0.0%, N = 17), which have previously been shown to be target organs during acute infections. Phylogenetic analysis showed homology betwe...

The study was carried out to assess pastoralists and agro-pastoralists awareness, knowledge and practice in various livestock diseases affecting domestic animals in Arusha Manyara and Morogoro regions in Tanzania. Closed- and open-ended questionnaires, focus group discussions and in-depth interview techniques were employed. Diseases, drought, lack of dipping tanks, insufficient of livestock experts and drugs are the main constraints in the livestock keeping community in the study area. Nineteen diseases have been reported to affect their animals at one time or the other. East Coast fever (ECF, 79.7%), Contagious Caprine Pleuropneumonia (CCPP, 60.8%) and Trypanosomosis (50%) have been reported by more than 50% of pastoralists that they affect their animals. ECF and CCPP seem to be the leading diseases with great impact to the pastoralists by causing high mortality rates. Rift valley fever (RVF) and anthrax have been reported by majority to be diseases which appear in form of outbreak...

Babesia species are protozoan parasites that parasitize the erythrocytes of domestic animals and humans, causing anemia in the host affected. These parasites cause a zoonotic disease known as babesiosis. Polymerase chain reaction (PCR) has proven to be very sensitive for detecting Babesia in blood samples of affected animals, particular in ruminants. The purpose of the current study was to determine the presence of Babesia DNA in the blood samples obtained from cattle, camel and sheep in Iran. In addition, the study aimed at establishing a rapid, reliable, specific and sensitive molecular tool, the PCR, for the detection of Babesia DNA in ruminants and dromedaries. Blood samples were collected from 372 ruminants and dromedaries (155 cattle, 95 sheep and 122 camel) kept at the Livestock Experimental Station. The animals came from randomly selected herds located in the important livestock-production regions of Iran of Isfahan and Chaharmahal va Bakhtiary during December 2012 to March ...

This study aimed to assess antimicrobial susceptibility of members of the family Flavobacteriaceae isolated from Nile tilapia (Oreochromis niloticus). Antimicrobial susceptibility of 67 Flavobacteriaceae isolates originating mainly from ponds and Lake Victoria against 19 antimicrobial agents was determined by the broth micro dilution method. Overall, most isolates were susceptible to enrofloxacin (97%; MIC90 2 μg/ml) followed by novobiocin (85%, MIC90, 4 μg/ml) and the aminoglycoside streptomycin (85%; MIC90, 128 μg/ml). Some isolates were also susceptible towards trimethoprim/sulfamethoxazole (77.6%), neomycin and florfenicol both at 62.7%. Susceptibility levels were low for tylosin tartrate (32.8%), clindamycin and sulphathiazole both at (23.9%), ceftiofur (6%), spectinomycin (6%) and tetracyclines/oxtetracyclines (4.5%). In contrast, β-Lactams (amoxicillin, penicillin), gentamycin and erythromycin exhibited very poor activity against Flavobacteriaceae isolates. The extent of anti...

In recent years, pig husbandry has gained ground in comparison to production of ruminant animals.  In Tanzania more than 90 per cent of the country’s two million pigs are kept by small-scale farmers under both confined and free-roaming management systems as a sole enterprise in urban areas or as a component of a mixed crop-livestock system.  Major constraints include poor management due to lack of knowledge by farmers, inadequate nutrition and limited veterinary services which result in heavy disease burdens.  At least 10 species of endo-parasites have been identified in Tanzania’s pig stock.  Mange mites, ticks, lice and fleas infest a large proportion of pigs.  Some five species of trypanosomes are blood parasites mainly in the northern part of the country.  Constraints imposed by these parasites must be mitigated in order to improve the productivity of pigs in the country.  This paper reviews the national literature on the subject.

Solid wastes comprise all the wastes arising from human and animal activities that are normally solid, discarded as useless or unwanted materials. Health hazards associated with improper disposal of solid wastes to the community were investigated in Morogoro municipality. The aim of the project was to investigate the solid waste disposal practices and their health hazard implications to the community in Morogoro municipality. The study was conducted by considering several solid waste disposal sites based on three methods; observation, questionnaire survey and microbiological analysis. Based on observation method, several solid waste practices were detected including collection of wastes using trucks, wheel barrow, carriers made from elephant grasses and cement bags. Questionnaire survey pinpointed several diseases caused by solid wastes such as malaria, diarrhea, dysentery, cholera, typhoid and worm diseases from the respondents. From microbiological analysis, several pathogenic bac...

Tilapia lake virus (TiLV) is a negative-sense single-stranded RNA (-ssRNA) icosahedral virus classified to be the only member in the family Amnoonviridae. Although TiLV segment-1 shares homology with the influenza C virus PB1 and has four conserved motifs similar to influenza A, B, and C polymerases, it is unknown whether there are other properties shared between TiLV and orthomyxovirus. In the present study, we wanted to determine whether TiLV agglutinated avian and piscine erythrocytes, and whether its replication was inhibited by lysosomotropic agents, such as ammonium chloride (NH4Cl), as seen for orthomyxoviruses. Our findings showed that influenza virus strain A/Puerto Rico/8 (PR8) was able to hemagglutinate turkey (Meleagris gallopavo), Atlantic salmon (Salmo salar L), and Nile tilapia (Oreochromis niloticus) red blood cells (RBCs), while infectious salmon anemia virus (ISAV) only agglutinated Atlantic salmon, but not turkey or tilapia, RBCs. In contrast to PR8 and ISAV, TiLV...

Solid wastes comprise all the wastes arising from human and animal activities that are normally solid, discarded as useless or unwanted materials. Health hazards associated with improper disposal of solid wastes to the community were investigated in Morogoro municipality. The aim of the project was to investigate the solid waste disposal practices and their health hazard implications to the community in Morogoro municipality. The study was conducted by considering several solid waste disposal sites based on three methods; observation, questionnaire survey and microbiological analysis. Based on observation method, several solid waste practices were detected including collection of wastes using trucks, wheel barrow, carriers made from elephant grasses and cement bags. Questionnaire survey pinpointed several diseases caused by solid wastes such as malaria, diarrhea, dysentery, cholera, typhoid and worm diseases from the respondents. From microbiological analysis, several pathogenic bacteria were identified from the solid disposal sites. The bacteria with their frequency of isolation identified were: Salmonella typhimurium (16.7%), Shigella dysenteriae (16.7%), Citrobacter freundii (8.3%), Citrobacter amalonaticus (8.3%), Aerobacter aerogenes (8.3%), Proteus vulgaris (16.7%), Klebsiella oxyotoca (8.3%), Klebsiella (8.3%), E.coli (8.3%). Solid waste generated by the daily activities of the people
needs to be properly managed in such a way that it minimizes the risk to the environment and human health. Inadequate collection and disposal of solid waste is a major factor in the spread of disease and environmental degradation.

Rift Valley fever (RVF) is an acute mosquito-borne
viral zoonotic disease affecting domestic animals and humans
caused by the Rift Valley fever virus (RVFV). The virus
belongs to the genus Phlebovirus of the family Bunyaviridae.
The main aim of this study was to detect the presence of
antibodies to RVFVas well as the virus in the serum samples
that were collected from livestock during the 2006/2007 RVF
outbreaks in different locations in Tanzania. Analysis of selected
samples was done using a RVF-specific inhibition
enzyme-linked immunosorbent assay (I-ELISA) and reverse
transcription polymerase chain reaction (RT-PCR). Genomic
viral RNAwas extracted directly from serum samples using a
QIAamp® Viral RNA Mini Kit (QIAGEN), and a one-step
RT-PCR protocol was used to amplify the S segment of
RVFV. Positive results were obtained in 39.5 % (n=200)
samples using the RVF I-ELISA, and 17.6 % (n=108) of
samples were positive by RT-PCR. I-ELISA detected 41
(38.7%), 32 (39.0%), and 6 (50.0 %) positive results in cattle,
goats, and sheep sera, respectively, whereas the RT-PCR
detected 11 (0.2 %), 7 (0.2 %), and 1 (0.1 %) positive results
in cattle, goats, and sheep sera, respectively. These findings
have demonstrated the presence of RVFV in Tanzania during the 2006/2007 RVF outbreaks. To our knowledge, this is the
first report to detect RVFV in serum samples from domestic
animals in Tanzania using PCR technique. Therefore, a detailed
molecular study to characterize the virus from different
geographical locations in order to establish the profile of
strains circulating in the country and develop more effective
and efficient control strategies should be done.

The circulation of infectious diseases in the community settings in urban and rural areas remains to be a hectic problem. One of the sources of microbial diseases is toilets. This study aimed at isolating, identifying and establishing bacterial loads associated with public restrooms in students’ hostels at Sokoine University of Agriculture in Morogoro, Tanzania. Samples were collected from a total of thirty toilets (60 samples) in different surfaces; (i) surfaces associated with toilets (toilet seats and toilet bowls), (ii) surfaces routinely touched with hands (door handles in and out of the restrooms, faucet handles and toilet flush handles) and (iii) the restroom floors. Samples were inoculated in MacConkey and Blood agar and then incubated at 37oC for 24 hours. All isolates were sub cultured and identified based on macro- and micro-morphology and Standard Biochemical Tests. The establishment of total bacteria load was done using Standard Plate Count Method. The sensitivity testing of the isolates were carried out using the Disk Diffusion Method on nutrient agar plate. The following bacteria genera and species were isolated from the students’ toilets; Staphylococcus aureus (25.0%), Escherichia coli (36.7%), Pseudomonas aeruginosa (13.3%), Streptococcus pyogenes (6.7%), Proteus mirabilis (6.7%) and Klebsiella pneumonia (11.6%). The results from total bacterial count indicated that the surfaces routinely touched with hands had highest bacteria load compared to restroom floor and toilet seats. However, the differences of means among the surfaces were not statistically significant (P= 0.6762).  Sensitivity testing of the isolates against commonly used antibiotics in the study area showed that all bacterial isolates tested were resistant and intermediate resistant to at least one antibiotic.

The study was carried out to assess pastoralists and agro-pastoralists awareness, knowledge and practice in
various livestock diseases affecting domestic animals in Arusha Manyara and Morogoro regions in Tanzania.
Closed- and open-ended questionnaires, focus group discussions and in-depth interview techniques were
employed. Diseases, drought, lack of dipping tanks, insufficient of livestock experts and drugs are the main
constraints in the livestock keeping community in the study area. Nineteen diseases have been reported to affect
their animals at one time or the other. East Coast fever (ECF, 79.7%), Contagious Caprine Pleuropneumonia
(CCPP, 60.8%) and Trypanosomosis (50%) have been reported by more than 50% of pastoralists that they affect
their animals. ECF and CCPP seem to be the leading diseases with great impact to the pastoralists by causing
high mortality rates. Rift valley fever (RVF) and anthrax have been reported by majority to be diseases which
appear in form of outbreak in their area. Diseases reported here are said to be controlled primarily by treating
with various drugs and Oxytetracycline being a common drug of choice for most unknown diseases. Other
control methods include vaccination and deworming, dipping and spray of animals using acariceides. Livestock
experts have been reported to play little role in controlling common livestock diseases as majority of livestock
keepers tends to treat their animals. Veterinary experts seem to be important during outbreak of diseases or for
unknown diseases killing many animals. Eating of dead and improperly cooked meat together with un-boiled
milk was found to be common in the pastoral community. This could lead to the spread (if any) of zoonotic
diseases easily. Livestock keeping community is aware of most of common diseases circulating in their area but
the way they practice to control leads to failure of control of those diseases at individual and national level.
Devising a mechanism to educate them so that they know how to handle some common and reporting outbreak
diseases such as use of trained community animal health workers (CAHWs) will help control livestock diseases
in Tanzania.

Rift Valley fever (RVF) is a viral notifiable zoonotic disease primarily of domestic ruminants that causes significant
socio-economic impacts. Using the 2006–07 outbreak cases, this study aimed to establish the socio-economic
impact of RVF and assessing knowledge, attitude and practice of livestock keepers towards controlling RVF in
selected areas of Tanzania. Data were collected in Arusha, Manyara and Morogoro regions using questionnaires,
focus group discussions and in-depth interviews with key informants. Results indicate that there was little
knowledge on disease (all clinical signs scored <50%) and the difference between the three regions was statistically
significant (P = 0.00459). Socio-economic impacts of RVF shown by this study included; animal and human deaths,
disruption of livestock market chains, inability of pastoralists to achieve their daily demands, inability to obtain
protein leading to malnutrition and monetary loss at individual and national level during control of the disease.
These findings have demonstrated low knowledge of the community on RVF, thus, more education and
engagement is needed in order to develop more effective and efficient control strategies.