Report from the World Health Organization's immunization and vaccines related implementation research advisory committee (IVIR-AC) meeting, Geneva, 11-13 September 2023.

Evaluating vaccine-related research is critical to maximize the potential of vaccination programmes. The WHO Immunization and Vaccine-related Implementation Research Advisory Committee (IVIR-AC) provides an independent review of research that estimates the performance, impact and value of vaccines, with a particular focus on transmission and economic modelling. On 11-13 September 2023, IVIR-AC was convened for a bi-annual meeting where the committee reviewed research and presentations across eight different sessions. This report summarizes the background information, proceedings and recommendations from that meeting. Sessions ranged in topic from timing of measles supplementary immunization activities, analyses of conditions necessary to meet measles elimination in the South-East Asia region, translating modelled evidence into policy, a risk-benefit analysis of dengue vaccine, COVID-19 scenario modelling in the African region, therapeutic vaccination against human papilloma virus, the Vaccine Impact Modelling Consortium, and the Immunization Agenda 2030 vaccine impact estimates.

Quantifying antibiotic use in typhoid fever in India: a cross-sectional analysis of private sector medical audit data, 2013-2015.

OBJECTIVES: To estimate the antibiotic prescription rates for typhoid in India. DESIGN: Cross-sectional study. SETTING: Private sector primary care clinicians in India. PARTICIPANTS: The data came from prescriptions of a panel of 4600 private sector primary care clinicians selected through a multistage stratified random sampling accounting for the region, specialty type and patient turnover. The data had 671 million prescriptions for antibiotics extracted from the IQVIA database for the years 2013, 2014 and 2015. PRIMARY AND SECONDARY OUTCOME MEASURES: Mean annual antibiotic prescription rates; sex-specific and age-specific prescription rates; distribution of antibiotic class. RESULTS: There were 8.98 million antibiotic prescriptions per year for typhoid, accounting for 714 prescriptions per 100 000 population. Children 10-19 years of age represented 18.6% of the total burden in the country in absolute numbers, 20-29 year age group had the highest age-specific rate, and males had a higher average rate (844/100 000) compared with females (627/100 000). Ten different antibiotics accounted for 72.4% of all prescriptions. Cefixime-ofloxacin combination was the preferred drug of choice for typhoid across all regions except the south. Combination antibiotics are the preferred choice of prescribers for adult patients, while cephalosporins are the preferred choice for children and young age. Quinolones were prescribed as monotherapy in 23.0% of cases. CONCLUSIONS: Nationally representative private sector antibiotic prescription data during 2013-2015 indicate a higher disease burden of typhoid in India than previously estimated. The total prescription rate shows a declining trend. Young adult patients account for close to one-third of the cases and children less than 10 years account for more than a million cases annually.

Disparity in socio-economic status explains the pattern of self-medication of antibiotics in India: understanding from game-theoretic perspective.

The emergence of antimicrobial resistance has raised great concern for public health in many lower-income countries including India. Socio-economic determinants like poverty, health expenditure and awareness accelerate this emergence by influencing individuals' attitudes and healthcare practices such as self-medication. This self-medication practice is highly prevalent in many countries, where antibiotics are available without prescriptions. Thus, complex dynamics of drug- resistance driven by economy, human behaviour, and disease epidemiology poses a serious threat to the community, which has been less emphasized in prior studies. Here, we formulate a game-theoretic model of human choices in self-medication integrating economic growth and disease transmission processes. We show that this adaptive behaviour emerges spontaneously in the population through a self-reinforcing process and continual feedback from the economy, resulting in the emergence of resistance as externalities of human choice under resource constraints situations. We identify that the disparity between social-optimum and individual interest in self-medication is primarily driven by the effectiveness of treatment, health awareness and public health interventions. Frequent multiple-peaks of resistant strains are also observed when individuals imitate others more readily and self-medication is more likely. Our model exemplifies that timely public health intervention for financial risk protection, and antibiotic stewardship policies can improve the epidemiological situation and prevent economic collapse.

A Critical Analysis of Concentration and Competition in the Indian Pharmaceutical Market.

OBJECTIVES: It can be argued that with several players marketing a large number of brands, the pharmaceutical market in India is competitive. However, the pharmaceutical market should not be studied as a single market but, as a sum total of a large number of individual sub-markets. This paper examines the methodological issues with respect to defining the relevant market involved in studying concentration in the pharmaceutical market in India. Further, we have examined whether the Indian pharmaceutical market is competitive. METHODS: Indian pharmaceutical market was studied using PharmaTrac, the sales audit data from AIOCD-AWACS, that organises formulations into 5 levels of therapeutic classification based on the EphMRA system. The Herfindahl-Hirschman Index (HHI) was used as the indicator of market concentration. We calculated HHI for the entire pharmaceutical market studied as a single market as well as at the five different levels of therapeutic classification. RESULTS AND DISCUSSION: Whereas the entire pharmaceutical market taken together as a single market displayed low concentration (HHI = 226.63), it was observed that if each formulation is defined as an individual sub-market, about 69 percent of the total market in terms of market value displayed at least moderate concentration. Market should be defined taking into account the ease of substitutability. Since, patients cannot themselves substitute the formulation prescribed by the doctor with another formulation with the same indication and therapeutic effect, owing to information asymmetry, it is appropriate to study market concentration at the narrower levels of therapeutic classification.

Implications of private sector Hib vaccine coverage for the introduction of public sector Hib-containing pentavalent vaccine in India: evidence from retrospective time series data.

OBJECTIVE: Haemophilus influenzae type b (Hib) vaccine has been available in India's private sector market since 1997. It was not until 14 December 2011 that the Government of India initiated the phased public sector introduction of a Hib (and DPT, diphtheria, pertussis, tetanus)-containing pentavalent vaccine. Our objective was to investigate the state-specific coverage and behaviour of Hib vaccine in India when it was available only in the private sector market but not in the public sector. This baseline information can act as a guide to determine how much coverage the public sector rollout of pentavalent vaccine (scheduled April 2015) will need to bear in order to achieve complete coverage. SETTING: 16 of 29 states in India, 2009-2012. DESIGN: Retrospective descriptive secondary data analysis. DATA: (1) Annual sales of Hib vaccines, by volume, from private sector hospitals and retail pharmacies collected by IMS Health and (2) national household surveys. OUTCOME MEASURES: State-specific Hib vaccine coverage (%) and its associations with state-specific socioeconomic status. RESULTS: The overall private sector Hib vaccine coverage among the 2009-2012 birth cohort was low (4%) and varied widely among the studied Indian states (minimum 0.3%; maximum 4.6%). We found that private sector Hib vaccine coverage depends on urban areas with good access to the private sector, parent's purchasing capacity and private paediatricians' prescribing practices. Per capita gross domestic product is a key explanatory variable. The annual Hib vaccine uptake and the 2009-2012 coverage levels were several times higher in the capital/metropolitan cities than the rest of the state, suggesting inequity in access to Hib vaccine delivered by the private sector. CONCLUSIONS: If India has to achieve high and equitable Hib vaccine coverage levels, nationwide public sector introduction of the pentavalent vaccine is needed. However, the role of private sector in universal Hib vaccine coverage is undefined as yet but it should not be neglected as a useful complement to public sector services.