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  • Progress and Works in Progress: Update on Flavivirus Vaccine Development.

    Posted 2018-02-21 23:01:42 by: Mahammad A. Tafida

    Related Articles Progress and Works in Progress: Update on Flavivirus Vaccine Development. Clin Ther. 2017 Aug;39(8):1519-1536 Authors: Collins MH, Metz SW Abstract Most areas of the globe are endemic for at least one flavivirus, putting billions at risk for infection. This diverse group of viral pathogens causes a range of manifestations in humans from asymptomatic infection to hemorrhagic fever to encephalitis to birth defects and even death. Many flaviviruses are transmitted by mosquitos and have expanded in geographic distribution in recent years, with dengue virus being the most prevalent, infecting approximately 400 million people each year. The explosive emergence of Zika virus in Latin America in 2014 refocused international attention on this medically important group of viruses. Meanwhile, yellow fever has caused major outbreaks in Africa and South America since 2015 despite a reliable vaccine. There is no vaccine for Zika yet, and the only licensed dengue vaccine performs suboptimally in certain contexts. Further lessons are found when considering the experience with Japanese encephalitis virus, West Nile virus, and tickborne encephalitis virus, all of which now have protective vaccination in human or veterinary populations. Thus, vaccination is a mainstay of public health strategy for combating flavivirus infections; however, numerous challenges exist along the path from development to delivery of a tolerable and effective vaccine. Nevertheless, intensification of investment and effort in this area holds great promise for significantly reducing the global burden of disease attributable to flavivirus infection. PMID: 28754189 [PubMed - indexed for ...

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  • Importance of bovine mastitis in Africa.

    Posted 2018-02-21 23:01:42 by: Mahammad A. Tafida

    Related Articles Importance of bovine mastitis in Africa. Anim Health Res Rev. 2017 Jun;18(1):58-69 Authors: Motaung TE, Petrovski KR, Petzer IM, Thekisoe O, Tsilo TJ Abstract Bovine mastitis is an important animal production disease that affects the dairy industry globally. Studies have estimated the prevalence of this disease in approximately 30% of African countries, with the highest prevalence found in Ethiopia. This is despite the wide cattle distribution in Africa, and the largest number of dairy farms and herds in countries such as South Africa, Kenya and Uganda. Furthermore, the estimated financial losses due to direct and indirect impacts of bovine mastitis are lacking in this continent. Therefore, intensive research efforts will help determine the continent-wide economic impacts and advance careful monitoring of disease prevalence and epidemiology. Here, published cases supporting the occurrence and importance of bovine mastitis in certain regions of Africa are outlined. PMID: 28606203 [PubMed - indexed for ...

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  • PCR-based verification of positive rapid diagnostic tests for intestinal protozoa infections with variable test band intensity.

    Posted 2018-02-21 23:01:42 by: Mahammad A. Tafida

    Related Articles PCR-based verification of positive rapid diagnostic tests for intestinal protozoa infections with variable test band intensity. Acta Trop. 2017 Oct;174:49-55 Authors: Becker SL, Müller I, Mertens P, Herrmann M, Zondie L, Beyleveld L, Gerber M, du Randt R, Pühse U, Walter C, Utzinger J Abstract Stool-based rapid diagnostic tests (RDTs) for pathogenic intestinal protozoa (e.g. Cryptosporidium spp. and Giardia intestinalis) allow for prompt diagnosis and treatment in resource-constrained settings. Such RDTs can improve individual patient management and facilitate population-based screening programmes in areas without microbiological laboratories for confirmatory testing. However, RDTs are difficult to interpret in case of 'trace' results with faint test band intensities and little is known about whether such ambiguous results might indicate 'true' infections. In a longitudinal study conducted in poor neighbourhoods of Port Elizabeth, South Africa, a total of 1428 stool samples from two cohorts of schoolchildren were examined on the spot for Cryptosporidium spp. and G. intestinalis using an RDT (Crypto/Giardia DuoStrip; Coris BioConcept). Overall, 121 samples were positive for G. intestinalis and the RDT suggested presence of cryptosporidiosis in 22 samples. After a storage period of 9-10 months in cohort 1 and 2-3 months in cohort 2, samples were subjected to multiplex PCR (BD Max™ Enteric Parasite Panel, Becton Dickinson). Ninety-three percent (112/121) of RDT-positive samples for G. intestinalis were confirmed by PCR, with a correlation between RDT test band intensity and quantitative pathogen load present in the sample. For Cryptosporidium spp., all positive RDTs had faintly visible lines and these were negative on PCR. The performance of the BD Max™ PCR was nearly identical in both cohorts, despite the prolonged storage at disrupted cold chain conditions in cohort 1. The Crypto/Giardia ...

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  • Effectiveness of three commonly used transition phase diets in the inpatient management of children with severe acute malnutrition: a pilot randomized controlled trial in Malawi.

    Posted 2018-02-21 11:02:40 by: Mahammad A. Tafida

    Related Articles Effectiveness of three commonly used transition phase diets in the inpatient management of children with severe acute malnutrition: a pilot randomized controlled trial in Malawi. BMC Pediatr. 2017 Apr 26;17(1):112 Authors: Versloot CJ, Voskuijl W, van Vliet SJ, van den Heuvel M, Carter JC, Phiri A, Kerac M, Heikens GT, van Rheenen PF, Bandsma RHJ Abstract BACKGROUND: The case fatality rate of severely malnourished children during inpatient treatment is high and mortality is often associated with diarrhea. As intestinal carbohydrate absorption is impaired in severe acute malnutrition (SAM), differences in dietary formulations during nutritional rehabilitation could lead to the development of osmotic diarrhea and subsequently hypovolemia and death. We compared three dietary strategies commonly used during the transition of severely malnourished children to higher caloric feeds, i.e., F100 milk (F100), Ready-to-Use Therapeutic Food (RUTF) and RUTF supplemented with F75 milk (RUTF + F75). METHODS: In this open-label pilot randomized controlled trial, 74 Malawian children with SAM aged 6-60 months, were assigned to either F100, RUTF or RUTF + F75. Our primary endpoint was the presence of low fecal pH (pH ≤ 5.5) measured in stool collected 3 days after the transition phase diets were introduced. Secondary outcomes were duration of hospital stay, diarrhea and other clinical outcomes. Chi-square test, two-way analysis of variance and logistic regression were conducted and, when appropriate, age, sex and initial weight for height Z-scores were included as covariates. RESULTS: The proportion of children with acidic stool (pH ≤5.5) did not significantly differ between groups before discharge with 30, 33 and 23% for F100, RUTF and RUTF + F75, respectively. Mean duration of stay after transitioning was 7.0 days (SD 3.4) with no differences between the three feeding strategies. ...

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  • Gastrointestinal parasites of canids, a latent risk to human health in Tunisia.

    Posted 2018-02-21 11:02:40 by: Mahammad A. Tafida

    Related Articles Gastrointestinal parasites of canids, a latent risk to human health in Tunisia. Parasit Vectors. 2017 Jun 05;10(1):280 Authors: Oudni-M'rad M, Chaâbane-Banaoues R, M'rad S, Trifa F, Mezhoud H, Babba H Abstract BACKGROUND: Although data on the parasite environmental contamination are crucial to implement strategies for control and treatment, information about zoonotic helminths is very limited in Tunisia. Contamination of areas with canid faeces harboring infective parasite elements represents a relevant health-risk impact for humans. The aim of this study was to assess the environmental contamination with eggs and oocysts of gastrointestinal parasites of dogs and wild canids in Tunisia with special attention to those that can be transmitted to humans. RESULTS: One thousand two hundred and seventy faecal samples from stray dogs and 104 from wild canids (red foxes and golden jackals) were collected from different geographical regions throughout Tunisia. The helminth eggs and protozoan oocysts were concentrated by sucrose flotation and identified by microscopic examination. The most frequently observed parasites in dog samples were Toxocara spp. (27.2%), E. granulosus (25.8%), and Coccidia (13.1%). For wild canid faeces, the most commonly encountered parasites were Toxocara spp. (16.3%) followed by Capillaria spp. (9.6%). The parasite contamination of dog faeces varied significantly from one region to another in function of the climate. CONCLUSION: To our knowledge, the study highlights for the first time in Tunisia a serious environmental contamination by numerous parasitic stages infective to humans. Efforts should be made to increase the awareness of the contamination risk of such parasites in the environment and implement a targeted educational program. PMID: 28583158 [PubMed - indexed for ...

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  • Antimicrobial resistance patterns of Staphylococcus species isolated from cats presented at a veterinary academic hospital in South Africa.

    Posted 2018-02-21 11:02:39 by: Mahammad A. Tafida

    Related Articles Antimicrobial resistance patterns of Staphylococcus species isolated from cats presented at a veterinary academic hospital in South Africa. BMC Vet Res. 2017 Sep 15;13(1):286 Authors: Qekwana DN, Sebola D, Oguttu JW, Odoi A Abstract BACKGROUND: Antimicrobial resistance is becoming increasingly important in both human and veterinary medicine. This study investigated the proportion of antimicrobial resistant samples and resistance patterns of Staphylococcus isolates from cats presented at a veterinary teaching hospital in South Africa. Records of 216 samples from cats that were submitted to the bacteriology laboratory of the University of Pretoria academic veterinary hospital between 2007 and 2012 were evaluated. Isolates were subjected to antimicrobial susceptibility testing against a panel of 15 drugs using the disc diffusion method. Chi square and Fisher's exact tests were used to assess simple associations between antimicrobial resistance and age group, sex, breed and specimen type. Additionally, associations between Staphylococcus infection and age group, breed, sex and specimen type were assessed using logistic regression. RESULTS: Staphylococcus spp. isolates were identified in 17.6% (38/216) of the samples submitted and 4.6% (10/216) of these were unspeciated. The majority (61.1%,11/18) of the isolates were from skin samples, followed by otitis media (34.5%, 10/29). Coagulase Positive Staphylococcus (CoPS) comprised 11.1% (24/216) of the samples of which 7.9% (17/216) were S. intermedius group and 3.2% (7/216) were S. aureus. Among the Coagulase Negative Staphylococcus (CoNS) (1.9%, 4/216), S. felis and S. simulans each constituted 0.9% (2/216). There was a significant association between Staphylococcus spp. infection and specimen type with odds of infection being higher for ear canal and skin compared to urine specimens. There were higher proportions of samples resistant to ...

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  • Subcutaneous dirofilariosis (Dirofilaria repens): an infection spreading throughout the old world.

    Posted 2018-02-16 11:02:02 by: Mahammad A. Tafida

    Related Articles Subcutaneous dirofilariosis (Dirofilaria repens): an infection spreading throughout the old world. Parasit Vectors. 2017 Nov 09;10(Suppl 2):517 Authors: Genchi C, Kramer L Abstract BACKGROUND: Two main Dirofilaria species infect dogs: D. immitis and D. repens. While D. immitis has a worldwide distribution, D. repens is currently found only in Europe, Asia, and Africa. Adult D. repens are located in subcutaneous tissues of natural hosts where they survive for long periods of time. First-stage larvae, microfilariae, circulate in the peripheral bloodstream, where they are taken up by the mosquito intermediate hosts. Infected mosquitoes then transmit infective third-stage (L3) larvae to new hosts through the blood meal. In dogs, most infections are asymptomatic, although cutaneous disorders such as pruritus, dermal swelling, subcutaneous nodules, and ocular conjunctivitis can be observed. Currently, two factors have increased the concerns about this parasitic infection 1) its spread throughout the European countries and to other continents and its prevalence in dog populations, where in some cases it has overcome D. immitis; and 2) its zoonotic potential, which is much greater than that of D. immitis. RESULTS: Different hypotheses can be put forward to explain these concerns. First, climate change has allowed more favorable conditions for survival of culicid vectors. Second, accidental hosts such as humans may have a less efficient immune reaction against a parasite that is located in subcutaneous tissues, and thus less exposed to the host's immune response than, for instance, D. immitis. Furthermore, the absence of clinical signs in the majority of canine infections and the difficulty in diagnosing the infection, due to the lack of serologic tests and thus the reliance on the identification of microfilariae and differentiation from D. immitis to confirm the presence of the parasite, favor ...

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