Onchocerca - infected cattle produce strong antibody responses to excretory-secretory proteins released from adult male Onchocerca ochengi worms

Haemophilus influenzae type b and pneumococcal conjugate vaccination coverage in children aged 2-59 months in Malawi

High vaccination coverage with Haemophilus influenzae type b (Hib) and pneumococcal conjugate vaccines is critical to addressing childhood pneumonia’s high mortality. The Innovative Treatments in Pneumonia project in Lilongwe, Malawi collected Hib and pneumococcal vaccination information from children’s health passports and found the majority demonstrated inadequate and inconsistent documentation. We were unable to confidently assess the impact of Hib and pneumococcal vaccination on pneumonia treatment failure in our study population. Whether it be that enrolled children did not receive age-eligible vaccines or there was poor vaccination record-keeping, we do not know. A shift to an electronic data collection system may help ensure capture of essential vaccination data and provide more accurate records of both individual and population vaccination coverage in Malawi.

Galectins from Onchocerca ochengi and O. volvulus and their immune recognition by Wistar rats, Gudali zebu cattle and human hosts

Background

During the last two decades research on animal filarial parasites, especially Onchocerca ochengi, infecting cattle in savanna areas of Africa revealed that O. ochengi as an animal model has biological features that are similar to those of O. volvulus, the aetiological agent of human onchocerciasis. There is, however, a paucity of biochemical, immunological and pathological data for O. ochengi. Galectins can be generated by parasites and their hosts. They are multifunctional molecules affecting the interaction between filarial parasites and their mammalian hosts including immune responses. This study characterized O. ochengi galectin, verified its immunologenicity and established its immune reactivity and that of Onchocerca volvulus galectin.

Results

The phylogenetic analysis showed the high degree of identity between the identified O. ochengi and the O. volvulus galectin-1 (ß-galactoside-binding protein-1) consisting only in one exchange of alanine for serine. O. ochengi galectin induced IgG antibodies during 28 days after immunization of Wistar rats. IgG from O. ochengi-infected cattle and O. volvulus-infected humans cross-reacted with the corresponding galectins. Under the applied experimental conditions in a cell proliferation test, O. ochengi galectin failed to significantly stimulate peripheral blood mononuclear cells (PBMCs) from O. ochengi-infected cattle, regardless of their parasite load.

Conclusion

An O. ochengi galectin gene was identified and the recombinantly expressed protein was immunogenic. IgG from Onchocerca-infected humans and cattle showed similar cross-reaction with both respective galectins. The present findings reflect the phylogenetic relationship between the two parasites and endorse the appropriateness of the cattle O. ochengi model for O. volvulus infection research.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-020-02064-3.

Entomological Assessment of Onchocerca Species Transmission by Black Flies in Selected Communities in the West Region of Cameroon

The enormity of the public health burden of onchocerciasis motivated the creation of various large-scale control programs that have depended principally on mass treatment of endemic communities with ivermectin for the elimination of the disease. Parasitological evaluation of Onchocerca species in the West Region of Cameroon indicates significant progress in the interruption of parasite transmission in some communities under ivermectin treatment. However, to verify the complete elimination of onchocerciasis, entomological assessment through O-150 PCR poolscreen of black flies is mandatory. Thus, in the present study, we assessed transmission of Onchocerca species using an O-150 PCR technique to screen pools of black flies—in seven onchocerciasis endemic communities (Makouopsap, Bankambe, Lemgo, Tsesse, Ndionzou, Kouffen, and Bayon) in Cameroon. Two thousand black flies were assessed—in each community—for the presence of Onchocerca species DNA. Our results show that the frequency of infective flies was 0.6% in Makouopsap and 0.0% in the other communities. On the other hand, the frequency of infected flies was 0.8% in Makouopsap, 0.2% in Bankambe, 0.1% in Bayon, and 0.0% in Lemgo, Tsesse, Ndionzou, and Kouffen. These results provide entomologic evidence for continuous transmission of Onchocerca species in Makouopsap, risk of active transmission in Bankambe, and Bayon, and a suppressed transmission in the four other studied communities.

Review of the status and challenges associated with increasing influenza vaccination coverage among pregnant women in China

Influenza vaccination coverage in pregnant women in China remains low. In this review, we first provide an overview of the evidence for the use of influenza vaccination during pregnancy. Second, we discuss influenza vaccination policy and barriers to increased seasonal influenza vaccination coverage in pregnant women in China. Third, we provide case studies of successes and challenges of programs for increasing seasonal influenza vaccination in pregnant women from other parts of Asia with lessons learned for China. Finally, we assess opportunities and challenges for increasing influenza vaccination coverage among pregnant women in China.

A review of Dengvaxia®: development to deployment

Dengue is the world's most prevalent and important arboviral disease. More than 50% of the world's population lives at daily risk of infection and it is estimated more than 95 million people a year seek medical care following infection. Severe disease can manifest as plasma leakage and potential for clinically significant hemorrhage, shock, and death. Treatment is supportive and there is currently no licensed anti-dengue virus prophylactic or therapeutic compound. A single dengue vaccine, Sanofi Pasteur's Dengvaxia®, has been licensed in 20 countries but uptake has been poor. A safety signal in dengue seronegative vaccine recipients stimulated an international re-look at the vaccine performance profile, new World Health Organization recommendations for use, and controversy in the Philippines involving the government, regulatory agencies, Sanofi Pasteur, clinicians responsible for testing and administering the vaccine, and the parents of vaccinated children. In this review, we provide an overview of Dengvaxia's® development and discuss what has been learned about product performance since its licensure.

Identification and characterization of the Onchocerca volvulus Excretory Secretory Product Ov28CRP, a putative GM2 activator protein

Onchocerca volvulus is the nematode pathogen responsible for human onchocerciasis also known as "River blindness", a neglected tropical disease that affects up to 18 million people worldwide. Helminths Excretory Secretory Products (ESPs) constitute a rich repertoire of molecules that can be exploited for host-parasite relationship, diagnosis and vaccine studies. Here, we report, using a range of molecular techniques including PCR, western blot, recombinant DNA technology, ELISA, high performance thin-layer chromatography and mass spectrometry that the 28 KDa cysteine-rich protein (Ov28CRP) is a reliable component of the O. volvulus ESPs to address the biology of this parasite. We showed that (1) Ov28CRP is a putative ganglioside GM2 Activator Protein (GM2AP) conserved in nematode; (2) OvGM2AP gene is transcriptionally activated in all investigated stages of the parasitic life cycle, including larval and adult stages; (3) The full-length OvGM2AP was detected in in-vitro O. volvulus ESPs of adult and larval stages; (4) the mass expressed and purified recombinant OvGM2AP purified from insect cell culture medium was found to be glycosylated at asparagine 173 and lacked N-terminal signal peptide sequence; (5) the recombinant OvGM2AP discriminated serum samples of infected and uninfected individuals; (6) OvGM2AP competitively inhibits MUG degradation by recombinant β-hexosaminidase A but not MUGS, and could not hydrolyze the GM2 to GM3; (7) humoral immune responses to the recombinant OvGM2AP revealed a negative correlation with ivermectin treatment. Altogether, our findings suggest for the first time that OvGM2AP is an antigenic molecule whose biochemical and immunological features are important to gain more insight into our understanding of host-parasite relationship, as well as its function in parasite development at large.

Human papillomavirus genotypes and infection among women in Changzhou, China

Human papillomavirus (HPV) infection is a major cause of cervical cancer. HPV vaccine has been shown to be highly effective in preventing HPV infection, and understanding the genotypes of HPV infection can guide the utilization of HPV vaccine. This epidemiological study aimed to investigate the genotype distribution of HPV in HPV-positive female patients in Changzhou. This study enrolled HPV-positive female patients admitted at the Affiliated Changzhou No. 2 People's Hospital of Nanjing Medical University were enrolled in this study. HPV genotypes were identified via standard HPV DNA testing. The cohort comprised 5738 patients, that the predominant genotypes were HPV52 (13.4%), HPV16 (9.6%), HPV58 (8.8%), HPV81 (8.6%), and HPV53 (7.7%). HPV infection prevalence was the highest among those aged 41-45 y (16.6%), followed by those aged 31-35 y (15.1%) and 36-40 y (15.1%). In total, 46.8% of infections were found in women aged 31-45 y. The main genotypes of HPV infection upon physical examination or diagnosis of cervicitis and cervical cancer were HPV52, 16, 58, 81, and 53. HPV52, 16, 58, 81, and 53 are the most predominant genotypes of HPV infection. Further, HPV infection is most prevalent among women aged 31-45 y. Our findings provide experimental evidence for guiding HPV vaccination policy.

Age of Initiation and Patterns of Use among People Who Inject Drugs Welcomed in Harm Reduction Facilities in France from 2006 to 2015

This exploratory analysis of time-series cross-sectional data provides insights on trends in age at first injection among people who inject drugs in France, and on associations with recent risky injecting behaviors. Data were collected from a national survey conducted in harm reduction facilities in five phases between 2006 and 2015. Standardized questionnaires collected information on demographics, substance use, and route of administration, as well as lifetime and past-month injection. Descriptive and multilevel models were applied to account for the hierarchical structure of the data. Prevalence of lifetime and past-month injection remained stable over time, while the prevalence of daily injection increased significantly. Mean age at first injection only appeared to increase for data collected after 2010. Gender differences in mean age at first injection decreased over time, suggesting the development of converging patterns of initiation independent of sex. After controlling for covariates, early initiation of injection was unrelated to daily injection or material sharing, and associated with the number of recently injected substances. Early initiation is likely a predictor of injected polysubstance use. Findings are relevant to the planning, implementation, and evaluation of prevention programs.

Otolaryngologists and their role in vaccination for prevention of HPV associated head & neck cancer

As Otolaryngologists we have witnessed a rise in a new disease with human papilloma virus (HPV) associated oropharyngeal squamous cell carcinoma (OPSCC). As of 2018, HPV associated OPSCC has surpassed the incidence of HPV associated cervical cancer within the United States. Non-HPV related head and neck cancer is largely a preventable disease through avoidance of various environmental factors, and we have seen a significant decline in cancer rates through anti-tobacco campaigns and other public health efforts. Given the success of HPV vaccination campaigns and reduction in HPV associated cervical and other anogenital cancers, some would argue HPV OPSCC is largely a preventable disease through vaccination as well. The question remains is how do we as otolaryngologist, non-primary care providers yet surgeons for this disease, help to promote public health efforts to reduce HPV related OPSCC. Within this article, we discuss preliminary data that supports HPV vaccination with HPV related OPSCC and the ongoing needs by our profession to help support public efforts in reducing the burden of this HPV related cancer.