Rubella virus, Toxoplasma gondii and Treponema pallidum congenital infections among full term delivered women in an urban area of Tanzania: a call for improved antenatal care

Background: A significant proportion of newborns in the developing countries are born with congenital anomalies.Objective: This study investigated congenital infections due to Rubella virus, Toxoplasma gondii, Treponema pallidum among presumed normal neonates from full term pregnant women in Mwanza, Tanzania.Methods: Sera from mothers were tested for Treponema pallidum and Toxoplasma gondii infection while newborns from mothers with acute infections were tested for T. pallidum and T. gondii, and all newborns were tested for Rubella IgM antibodies.Results: A total of 13/300 (4.3 %) mothers had T. pallidum antibodies with 3 of them having acute infection. Two (0.7 %) of the newborns from mothers with acute infection were confirmed to have congenital syphilis. Regarding toxoplasmosis, 92/300 (30.7 %) mothers were IgG seropositive and 7 had borderline positivity, with only 1/99 (1%) being IgM seropositive who delivered IgM seronegative neonate. Only 1/300 (0.3 %) newborn had rubella IgM antibodies indicating congenital rubella infection.Conclusion: Based on these results, it is estimated that in Mwanza city in every 100,000 live births about 300 and 600 newborns have congenital rubella and syphilis infections, respectively. Rubella virus and T. pallidum are likely to be among common causes of congenital infections in developing countries.Keywords: Congenital infections, Mwanza, Tanzania

Rubella seromarkers and determinants of infection among tanzanian children and adolescents in prevaccination Era: Are we in the right track?

Background: The World health organization advocates assessment of the burden of rubella and congenital rubella syndrome (CRS) by seroepidemiological surveys and surveillance programs in all countries without vaccination programs. Due to scarcity of data in developing countries, this study was conducted to assess the seromakers for natural rubella infection in Tanzania during prevaccination era so as to ascertain the gaps for future research and prevention strategies. Methods: A cross-sectional study was conducted between September and October 2014. Indirect enzyme-linked immunosorbent assay was used to detect rubella IgG and IgM antibodies. STATA version 11 was used to perform data analysis. Results: Of 723 enrolled participants, 368 (50.8%) and 94 (13%) were positive for specific IgG and IgM rubella antibodies, respectively. On multivariable logistic regression analysis, significant determinants of rubella IgG seropositivity were increase in age (odds ratios [OR]: 1.24, 95% confidence interval [CI]: 1.18-1.29, P < 0.001), low socioeconomic status (SES) (OR: 2.38, 95% CI: 1.1.23-4.50, P = 0.010), and absence of rash (OR: 4.34, 95% CI: 1.1.17-15.3, P = 0.027), while only the presence of rashes was significant determinant of rubella IgM seropositivity (OR: 2.5, 95%; 1.07-5.98, P = 0.034). Significantly higher mean IgG titers were observed in population ≥10 years (P < 0.001), those residing in urban and peri-urban areas (P < 0.001), those from employed mothers (P = 0.018), and those with no current history of fever (P = 0.018). Conclusions: The prevalence of specific rubella IgG antibodies in Tanzania is high and is associated with increase in age, absence of rash, and low SES. Results suggest a need to reconsider upper age limit for vaccination campaigns in developing countries. Screening and vaccinating women may be cost-effective campaign to prevent CRS in developing countries

The Campylobacter jejuni Cj0268c protein is required for adhesion and invasion in vitro.

Adherence of Campylobacter jejuni to its particular host cells is mediated by several pathogen proteins. We screened a transposon-based mutant library of C. jejuni in order to identify clones with an invasion deficient phenotype towards Caco2 cells and detected a mutant with the transposon insertion in gene cj0268c. In vitro characterization of a generated non-random mutant, the mutant complemented with an intact copy of cj0268c and parental strain NCTC 11168 confirmed the relevance of Cj0268c in the invasion process, in particular regarding adherence to host cells. Whereas Cj0268c does not impact autoagglutination or motility of C. jejuni, heterologous expression in E. coli strain DH5α enhanced the potential of the complemented E. coli strain to adhere to Caco2 cells significantly and, thus, indicates that Cj0268c does not need to interact with other C. jejuni proteins to develop its adherence-mediating phenotype. Flow cytometric measurements of E. coli expressing Cj0268c indicate a localization of the protein in the periplasmic space with no access of its C-terminus to the bacterial surface. Since a respective knockout mutant possesses clearly reduced resistance to Triton X-100 treatment, Cj0268c contributes to the stability of the bacterial cell wall. Finally, we could show that the presence of cj0268c seems to be ubiquitous in isolates of C. jejuni and does not correlate with specific clonal groups regarding pathogenicity or pathogen metabolism