Typhoid vaccination: A curtain raiser & IAPCOI perspectives Vipin M. Vashishtha, MD, FIAP Convener, IAPCOI August 24 th & 25 th 2012 Mid-term Meeting of IAPCOI, The Hyatt Regency Hotel, Mumbai
Is typhoid indeed a serious public health problem in India to merit vaccination?
Crude typhoid fever incidence rates by region, 2000
Incidence rate of typhoid fever in Asia: comparison of 2 multi-centre trials
Incidence of Typhoid in India Kothari et al. The burden of enteric fever 259 J Infect Developing Countries 2008; 2(4):
Age-specific incidence of culture-proven typhoid fever from population-based studies Bhan MKBhan MK, Bahl R, Bhatnagar S. Typhoid and paratyphoid fever. Lancet ;366(9487): Bahl RBhatnagar SLancet.
Characteristics and incidence of typhoid fever from the study sites: Age group Ochiai RL, Acosta CJ, Danovaro-Holliday MC et al. (2008) A study of typhoid fever in five Asian countries: disease burden and implications for control. Bull World Health Organ 86(4): SiteHechi, China Kolkata India North Jakarta Indonesia Karachi Pakistan Hue, Viet Nam Total Typhoid Incidence (per /yr) by age yearsNA NA yearsNA NA years ≥ 16 years NA
How big is the paratyphoid burden?
Trends in S. Paratyphi A, Safdarjung Hospital (S. Typhi vs. S. Paratyphi A) J Infect Dev Ctries 2010; 4(6):
Typhoid: Antibiotics resistance
Global distribution of antimicrobial resistance in S typhi (1990–2004)
Rates of Antibiotic Resistance among S. Typhi Isolates from Five Asian Study Sites in the DOMI Programme
Studies reporting high-level ciprofloxacin resistance in S. typhi & S. paratyphi A in India Harish BN, Menezes GA. Indian J Med Microbiol Jul-Sep;29(3):223-9.
Typhoid fever: Our scenario
Mangla Hospital & Research Center Bijnor a small city of western Uttar Pradesh, a northern state of India District population (2007): 3.4 million Decadal population growth (2007)= 27.16%; UP=25.8%, India=21.34% Birth rate: 460 per 10,000; UP=382, India=268 Females ratio: 896 per 1000 males, UP=898; Inia=933 Delivery at hospitals/nursing homes: 28.7%; India= 40.7%
A sentinel site surveillance of 10 VPDs
Total OPD cases, March 2011-May 2012
* Till May 18, % of all 10 VPDS!!
Age group of typhoid cases (N=382)
Immunization status (N=382)
Seasonal breakup: March 2011-May 2012
Arguments against significant typhoid burden in India
Non-believers!!!
Significance of Typhoid in India* 1. Ochiai RL, Acosta CJ, Danovaro-Holliday MC, Baiqing D, Bhattacharya SK, Agtini MD, et al. A study of typhoid fever in five Asian countries: disease burden and implications for controls. Bull WHO 2008; 86: *Mathew JL. Conjugate typhoid vaccine(s) in the Indian context. Indian Pediatr Feb;46(2): Indian Pediatr.
Do we need typhoid vaccination?
Justification for Typhoid vaccination Problem - I Globally about 21.6 million cases every year, causing about 2.1 lac deaths But estimates indicate 33 million cases 90% of all cases and deaths in Asia, rest in Africa and Latin America Problem – II Multi drug resistance Problem – III Changing age scenario – infants and toddlers equally affected
Do we have ‘effective’ typhoid vaccine to issue recommendations on widespread use?
Orphan disease & Neglected vaccine!!
Vaccination against typhoid Evidence from Cuba, Iran, Thailand, Malaysia, Vietnam, & China confirms that a one-dose, Vi- PS vaccination strategy targeting a wide age range can effectively control disease However, only 6 countries currently have school or community-based typhoid vaccination programs
Vi-PS typhoid vaccine has shown effectiveness in India!! In a recently published cluster randomized effectiveness trial conducted in over 40,000 subjects in urban slums of Kolkata, the overall effectiveness of the vaccine at 2 years follow up was 61%, and in children below 5 years was 80% Interestingly the herd protection of 44% was noted in unvaccinated children in the vaccinated cluster as compared to the control cluster Dipika Sur, R. Leon Ochiai, et al. A Cluster-Randomized Effectiveness Trial of Vi Typhoid Vaccine in India. N Engl J Med 2009;361:
What about the currently available Indian Vi-PS conjugate vaccine? Does it have any role? Can we improve it further?
What is the pipeline for next generation typhoid vaccines?
Geographic Representation of Typhoid Vaccination Programs Despite recommendations, typhoid vaccines are significantly underutilized!!!
Barriers to widespread typhoid vaccine use: Other potential challenges: Paratyphi burden? Lack of WHO prequalified vaccines Country political will Managing typhoid as a communicable disease rather than within the immunization system Current focus on Hib, pneumococcal, and rotavirus vaccine introduction in GAVI countries
How can IAPCOI help in prevention of Typhoid fever in India? Can we initiate a collaborative project with international agencies/institutions? What level of support/commitment is required?
Thank You!