The role of vaccines in reducing antimicrobial resistance: A review of potential impact of vaccines on AMR and insights across 16 vaccines and pathogens.

In 2019, an estimated 4.95 million deaths were linked to antimicrobial resistance (AMR). Vaccines can prevent many of these deaths by averting both drug-sensitive and resistant infections, reducing antibiotic usage, and lowering the likelihood of developing resistance genes.

Typhoid Fever Surveillance, Incidence Estimates, and Progress Toward Typhoid Conjugate Vaccine Introduction - Worldwide, 2018-2022.

Typhoid fever, an acute febrile illness caused by Salmonella enterica serovar Typhi (S. Typhi), is endemic in many low- and middle-income countries (1). In 2015, an estimated 11-21 million typhoid fever cases and 148,000-161,000 associated deaths occurred worldwide (2).

Evaluation of Vaccine Safety After the First Public Sector Introduction of Typhoid Conjugate Vaccine-Navi Mumbai, India, 2018.

Background: In December 2017, the World Health Organization (WHO) prequalified the first typhoid conjugate vaccine (TCV; Typbar-TCV). While no safety concerns were identified in pre- and postlicensure studies, WHO's Global Advisory Committee on Vaccine Safety recommended robust safety evaluation with large-scale TCV introductions. During July-August 2018, the Navi Mumbai Municipal Corporation (NMMC) launched the world's first public sector TCV introduction.

Typhoid Outbreaks, 1989-2018: Implications for Prevention and Control.

Typhoid fever remains an important public health problem in low- and middle-income countries, with large outbreaks reported from Africa and Asia. Although the WHO recommends typhoid vaccination for control of confirmed outbreaks, there are limited data on the epidemiologic characteristics of outbreaks to inform vaccine use in outbreak settings. We conducted a literature review for typhoid outbreaks published since 1990.

Toward Control? The Prospects and Challenges of Typhoid Conjugate Vaccine Introduction.

With a newly World Health Organization (WHO)-prequalified typhoid conjugate vaccine (TCV), Gavi funding for eligible countries, and a WHO policy recommendation for TCV use, now is the time for countries to introduce TCVs as part of an integrated typhoid control program, particularly in light of the increasing burden of antimicrobial resistance. Continued vaccine development efforts will lead to secure supply of low-cost vaccines, and ongoing vaccine studies will provide critical vaccine performance data and inform optimal deployment strategies, in both routine use and in outbreak settings. TCV programs should include thoughtful communication planning and community engagement to counter vaccine hesitancy.

Accelerating Typhoid Conjugate Vaccine Introduction: What Can Be Learned From Prior New Vaccine Introduction Initiatives?

The health consequences of typhoid, including increasing prevalence of drug-resistant strains, can stress healthcare systems. While vaccination is one of the most successful and cost-effective health interventions, vaccine introduction can take years and require considerable effort. The Typhoid Vaccine Acceleration Consortium (TyVAC) employs an integrated, proactive approach to accelerate the introduction of a new typhoid conjugate vaccine to reduce the burden of typhoid in countries eligible for support from Gavi, the Vaccine Alliance.

Revised Global Typhoid Vaccination Policy.

Typhoid fever is a continuing public health problem in many low- and middle-income countries; however, routine vaccination as a recommended control strategy has not been implemented in the past in most countries. Greater understanding of the typhoid fever burden, the increasing threat of antimicrobial resistance, and licensure of a new generation of typhoid conjugate vaccines (TCVs) were instrumental in paving the way for the World Health Organization (WHO) to issue a revised global policy on typhoid vaccines in March 2018. The new policy follows evidence-based recommendations by the WHO Strategic Advisory Group of Experts on immunization for routine and catch-up vaccination with TCVs and highlights considerations for universal, risk-based, or phased vaccination strategies in different settings.

Typhoid fever vaccination strategies.

Typhoid vaccination is an important component of typhoid fever prevention and control, and is recommended for public health programmatic use in both endemic and outbreak settings. We reviewed experiences with various vaccination strategies using the currently available typhoid vaccines (injectable Vi polysaccharide vaccine [ViPS], oral Ty21a vaccine, and injectable typhoid conjugate vaccine [TCV]). We assessed the rationale, acceptability, effectiveness, impact and implementation lessons of these strategies to inform effective typhoid vaccination strategies for the future.

Typhoid Fever surveillance and vaccine use - South-East Asia and Western Pacific regions, 2009-2013.

Typhoid fever is a serious, systemic infection resulting in nearly 22 million cases and 216,500 deaths annually, primarily in Asia. Safe water, adequate sanitation, appropriate personal and food hygiene, and vaccination are the most effective strategies for prevention and control. In 2008, the World Health Organization (WHO) recommended use of available typhoid vaccines to control endemic disease and outbreaks and strengthening of typhoid surveillance to improve disease estimates and identify high-risk populations (e.

Long-term safety assessment of live attenuated tetravalent dengue vaccines: deliberations from a WHO technical consultation.

Dengue is a rapidly growing public health threat with approximately 2.5 billion people estimated to be at risk. Several vaccine candidates are at various stages of pre-clinical and clinical development.

An outbreak of severe infections with community-acquired MRSA carrying the Panton-Valentine leukocidin following vaccination.

Background: Infections with community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) are emerging worldwide. We investigated an outbreak of severe CA-MRSA infections in children following out-patient vaccination.

Methods And Findings: We carried out a field investigation after adverse events following immunization (AEFI) were reported.

Monitoring of adverse events during the 2003 mass vaccination campaign with a trivalent meningococcal A/C/W135 polysaccharide vaccine in Burkina Faso.

During a mass campaign with a newly licensed meningococcal polysaccharide ACW135 vaccine in Burkina Faso, adverse events following immunization (AEFI) were monitored up to 4 weeks after the campaign. Eighty-six AEFI cases (5.9 cases per 100,000 vaccine doses distributed) were reported.

Monitoring vaccine safety during measles mass immunization campaigns: clinical and programmatic issues.

In the planning and implementation of mass immunization campaigns, vaccine delivery has always been a priority. However, safety issues have gained increasingly more attention and grown in importance, and campaign planners must now take them into prime consideration. The World Health Organization has released guidelines to assist with the design and implementation of safety surveillance systems, primarily for developing countries, and these include a new monograph for measles mass campaigns.

Protocol for the investigation of acute flaccid paralysis and suspected paralytic poliomyelitis.

Despite the elimination of indigenous wild poliovirus in Canada, ongoing surveillance for poliomyelitis is important because of the risk of wild virus importation from endemic regions. Most recently, importation of wild poliovirus into Canada occurred in 1993 and 1996,inboth instances with no associated clinical illness. Since 1991, the active surveillance of acute flaccid paralysis (AFP) in children less than 15 years old has been carried out in Canada to monitor for suspected cases of paralytic poliomyelitis.

Vaccination coverage levels among children two years of age and selected aspects of vaccination practices in Canada - 1996.

Objective: To obtain population-based estimates of coverage for routine childhood vaccinations at two years of age and information about selected aspects of vaccination practices in Canada.

Methods: Data were collected through a mail survey of a sample of households with two-year-olds born between February 1993 and January 1994. To obtain population estimates, survey data were weighted to match known population distributions of geographic region, community size, household income level and single-parent versus two-parent family type.

Estimates of the effectiveness of a whole-cell pertussis vaccine from an outbreak in an immunized population.

Pertussis has re-emerged as a public health problem in Canada in recent years, emphasizing concerns about the effectiveness of the currently licensed whole-cell vaccine. Following a 1994 outbreak in Nova Scotia, we conducted a case-control study of 483 children aged < 10 years to assess vaccine effectiveness. Ninety-three percent of children aged 6 months and above had received three or more doses of vaccine, however, only 78% had received age-appropriate immunization.

Maternal knowledge, attitude and practices regarding childhood acute respiratory infections in Kumasi, Ghana.

Acute respiratory infections (ARI) are a major cause of paediatric mortality and morbidity, particularly when associated with delays in treatment. A study of mothers' knowledge, attitudes and practices regarding ARI in their children aged less than 5 years was conducted in an urban Ghanaian population. One hundred and forty-three women traders were interviewed in open air markers in Kumasi, Ghana.