August 10, 2021
Plant-based vaccine candidates pass clinical trials. In a Phase I clinical trial in Japan, a new oral cholera vaccine (MucoRice-CTB) grown in genetically modified rice demonstrated safety and efficacy in preventing diarrheal disease. Other plant-based vaccine candidates commonly grown in tobacco and lettuce plants also succeed in clinical trials and offer benefits to the vaccine field by simplifying the manufacturing process and not requiring cold-chain storage. Last year, a plant-based vaccine for influenza developed by the Canadian company Medicago became the first to pass Phase 3 clinical trials. Several vaccine candidates for COVID-19 are also currently in clinical trials. [The Lancet Microbe, The Lancet, National Geographic]
Typhoid vaccination campaign effective at curbing outbreak in Pakistan. A study led by researchers at Aga Khan University Hospital in Pakistan assessed the effectiveness and impact of the Typbar-TCV vaccine against S Typhi with extensive drug resistance (XDR) among children included in the census registry and surveillance system. Of the 23,407 children included in the study, 57.4% were vaccinated. Vaccine effectiveness was 55% against suspected infection, 95% against confirmed infection, and 97% against XDR S Typhi. [The Lancet]
Changes to essential medicine lists to effectively treat diseases and address AMR. A cross-sectional study assessed the WHO’s Access, Watch, and Reserve (AWaRe) antibiotics in 138 national essential medicines lists (NEML). A median of 26 essential antibiotics was listed in the countries’ NEMLs with a median of 35 AWaRe antibiotics: 18 Access, 16 Watch, and one from the Reserve category. Many countries (41% ) did not list any Reserve antibiotics warranting revisions of NEMLs to improve treatment and address antimicrobial resistance. [The Lancet]
Text reminders boost COVID-19 vaccine uptake. A US study investigated the impact of behavioral interventions on COVID-19 vaccine uptake through two sequential randomized controlled studies. Text reminders were sent to patients on days one and eight following vaccine eligibility. The researchers found that the first reminder was more impactful when it made people feel the vaccination was theirs, highlighting the importance of facilitating vaccine access and promoting a feeling of ownership. [Nature]
Pneumonia treatment imposes significant economic strains on Ugandan households. Researchers in Uganda estimated costs associated with an episode of pneumonia from various perspectives. The study showed that pneumonia treatment places an enormous economic burden on families; the average societal cost per episode was $42, with an increased cost of $62 in hospitalization cases. Those using the public system had lower out-of-pocket costs than those using private-for-profit or nonprofit care; however, for 39% of households, out-of-pocket expenses for pneumonia episodes were of catastrophic proportions, consisting of more than 40% of household expenditure. [Vaccine X]
Secondary attack rate lower for contacts of index cases without respiratory symptoms. A prospective cohort study estimated secondary attack rates (SARs) following household contact with COVID-19 infection in adults and children. SAR among 431 contacts of 172 symptomatic index cases was lower from primary cases without respiratory symptoms (6% vs. 37%). Although symptom development was consistent across age (78%), the mean number of symptoms was lower for those less than 19 years old. [Journal of Infection]
CDC report on the safety of Pfizer COVID-19 vaccine in adolescents consistent with initial findings from clinical trials. Following a safety assessment of the Pfizer-BioNTech COVID-19 vaccine in adolescents aged 12-17 years, the CDC continues to recommend the vaccine for persons aged 12 years and older. Mild, local, and systemic reactions were most common after the second dose (90.7%), while severe symptoms were rare (9.3%), 40% of which were myocarditis, previously seen after vaccination with mRNA vaccines. Overall, the safety findings of the CDC study matched those from the clinical trials. [CDC]
High rates of drug-resistant tuberculosis in Sudan. A systematic review and meta-analysis developed an updated picture of the prevalence of drug-resistant tuberculosis (DR-TB) in Sudan. The prevalence of DR-TB to any anti-TB drugs was 47%. Resistance to at least one drug was higher among previously treated patients than in newly diagnosed TB patients (62.8% vs. 30.7%), highlighting the need for improvements in TB control and treatment strategies in Sudan. [Antibiotics]
Seven-day antibiotic treatment for UTIs in afebrile men is just as effective as a 14-day treatment. A randomized clinical trial tested the effectiveness of a 7-day vs. 14-day antibiotic treatment duration for UTIs in afebrile men. By day 7, the overwhelming majority of the patients in both groups had their symptoms resolved (93.1% vs. 90.2%), and symptom recurrence occurred at similar rates. The 7-day treatment duration was non-inferior to the 14-day treatment, suggesting opportunities to reduce unnecessary use of antibiotics. [JAMA]
BNT162b2 vaccine effective in people living with HIV. A recent study evaluating the effectiveness of the BNT162b2 mRNA vaccine in people living with HIV revealed no significant difference in the titers of COVID-19 antibodies in healthy patients (median value of 9.49) compared to patients with HIV (median value of 8.84). In addition, both groups had similar levels of neutralizing antibodies to the vaccine strain spike protein and spike proteins from other COVID-19 variants of concern. Despite the small sample size (12 patients with HIV and 17 patients without), the study provides evidence of the effectiveness of the BNT162b2 mRNA vaccine in people living with HIV. [Clinical Infectious Diseases]
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