Hexavalent vaccines

Please consult the relevant WHO Position Papers for details on the burden of disease caused by each pathogen included in the combination vaccine.^{Go to footnote 11 Go to footnote 22, Go to footnote 33, Go to footnote 44, Go to footnote 55, Go to footnote 66}

For data on the reported cases of diphtheria, tetanus and pertussis, consult the WHO global immunization database for the most updated reported data by country, or WHO Region.^{Go to footnote 77}

The latest case counts of poliomyelitis cases can be found on the Global Polio Eradication Initiative (GPEI) website.^{Go to footnote 88, Go to footnote 99}

Please consult the relevant WHO Position Papers.^{Go to footnote 11 Go to footnote 22, Go to footnote 33, Go to footnote 44, Go to footnote 55, Go to footnote 66}

The combination hexavalent vaccine consists of antigens targeting six diseases. These antigens have been used individually or in combination in most countries over long periods of time. The proportion of the population affected by these diseases and the age distribution of cases vary depending on duration of vaccine use, the coverage levels achieved with the primary series and the recommended booster doses.^{Go to footnote 11, Go to footnote 22, Go to footnote 33, Go to footnote 44, Go to footnote 55, Go to footnote 66}

Please consult the relevant WHO Position Papers.^{Go to footnote 11, Go to footnote 22, Go to footnote 33, Go to footnote 44, Go to footnote 55, Go to footnote 66}

There are three types of polioviruses that cause poliomyelitis. These include wild poliovirus types as well as vaccine-derived viruses, which are related to each vaccine virus serotype in live attenuated vaccines regaining neurovirulence due to mutations in its genome.

Wild poliovirus (WPV) types 2 and 3 have been certified globally eradicated; WPV type 1 (WPV1) is the only remaining wild poliovirus serotype in circulation. Consult the GPEI website for the latest information on the reported cases of wild poliovirus type 1 (WPV1) and the different serotypes of circulating vaccine-derived polioviruses (cVDPV) ^{Go to footnote 1010 Go to footnote 1111}

For serotypes and/or genotypes of other organisms in the combination, please refer to the relevant position papers.

Please consult the relevant WHO Position Papers.^{Go to footnote 11, Go to footnote 22, Go to footnote 33, Go to footnote 44, Go to footnote 55, Go to footnote 66}

The number of reported or estimated deaths are available in the respective position papers or compendium sheets.^{Go to footnote 11, Go to footnote 22, Go to footnote 33, Go to footnote 44, Go to footnote 55, Go to footnote 66}

Ongoing updates of reported or estimates of deaths are available for Tetanus,^{Go to footnote 1212} Diphtheria and Pertussis.^{Go to footnote 1313}

Please consult the relevant WHO Position Papers.^{Go to footnote 11, Go to footnote 22, Go to footnote 33, Go to footnote 44, Go to footnote 55, Go to footnote 66}

Case fatality ratios of the diseases targeted by the hexavalent vaccines vary between diseases and across communities. Each individual disease can result in death. The reported case fatality ratios for each individual disease are reported in the respective position papers and are strongly influenced by access to and the quality of medical care.^{Go to footnote 11, Go to footnote 22, Go to footnote 33, Go to footnote 44, Go to footnote 55, Go to footnote 66}

Diphtheria, though largely controlled in many regions as a result of vaccination, can still cause outbreaks especially in populations with low immunization coverage, high mobility, or poor living conditions.^{Go to footnote 1414} Diphtheria outbreaks have been reported in various settings, including refugee camps in Asia, and among asylum seekers in Europe.^{Go to footnote 1515, Go to footnote 1616} Diphtheria outbreaks are also being reported in countries with high infant immunization coverage as a result of waning of immunity.^{Go to footnote 1717, Go to footnote 1818}

Because it is acquired through exposure to Clostridium tetani spores in the environment and is not transmitted from person to person, it does not generally cause outbreaks, although increased numbers of cases may occur following circumstances associated with contaminated wounds and disrupted health services.^{Go to footnote 1919}

Pertussis has a well-documented history of causing outbreaks, even in populations with high vaccination coverage. Recent trends show that pertussis continues to have significant outbreak potential worldwide, affecting both children and adults, and posing particular risks to infants.^{Go to footnote 2020, Go to footnote 2121} Countries using acellular pertussis (aP) vaccines have generally experienced larger pertussis resurgences than countries that continue to use whole-cell pertussis (wP) vaccines, but vaccine type is only one of several important factors. This is because aP vaccines are less effective in preventing asymptomatic infection and transmission of infection and protective immunity following aP vaccines wanes faster than following wP vaccines.^{Go to footnote 2222}

Hepatitis B has significant potential for outbreaks, especially in settings with poor infection control or low vaccination coverage. Outbreaks of hepatitis B have been documented in both healthcare and community settings, and the virus remains a persistent public health threat in many regions.^{Go to footnote 2323, Go to footnote 2424}

Hib has been associated with small outbreaks or clusters of Hib in day-care centres prior to widespread vaccination, along with reports of nosocomial transmission in hospitals. Large household size and crowding have also been identified as risk factors for invasive Hib disease in children.^{Go to footnote 2525, Go to footnote 2626, Go to footnote 2727}

Poliovirus has the potential to cause outbreaks and localized epidemics, with the risk remaining high in areas with low vaccination coverage, fragile health systems, or gaps in immunization campaigns, particularly in regions experiencing conflict or displacement.^{Go to footnote 66 Go to footnote 2828} Wild poliovirus (WPV) is endemic to Afghanistan and Pakistan, while vaccine-derived poliovirus (cVDPV) outbreaks have been reported in other countries.^{Go to footnote 66, Go to footnote 2929} Following the global withdrawal of type 2-containing OPV from routine immunization in 2016, gaps in population immunity to poliovirus type 2 have contributed to conditions that allow vaccine-derived type 2 polioviruses to emerge and circulate.^{Go to footnote 66, Go to footnote 2828} Although the global pandemic potential is low due to widespread immunity and effective vaccines, gaps in immunization and surveillance have led to the detection of poliovirus in environmental samples in previously polio-free countries.^{Go to footnote 2929 Go to footnote 2828, Go to footnote 3030, Go to footnote 3131}

There are no established global elimination goals for Diphtheria or Pertussis (some countries have defined control goals for Diphtheria). 

The Maternal and Neonatal Tetanus Elimination (MNTE) initiative, launched by the World Health Organization (WHO) in 1989, initially aimed to eliminate neonatal tetanus by 1995. As of December 2025, 51 of the 59 priority countries have achieved MNTE status, significantly reducing neonatal tetanus cases by 89% and deaths by 84% since 2000. Vaccination is the cornerstone of the strategy. Immunizing women of reproductive age with tetanus toxoid-containing vaccines (TTCVs) has been the primary driver of this reduction.^{Go to footnote 3232, Go to footnote 3333, Go to footnote 3434}

WHO has set a target to achieve hepatitis B elimination by 2030, aiming for a 90% reduction in new infections and a 65% reduction in deaths. Vaccination is the cornerstone in the global effort to eliminate Hepatitis B. Widespread and timely hepatitis B vaccination, especially starting at birth, dramatically reduces new infections, chronic disease, and deaths from liver complications. The prevalence of hepatitis B surface antigen (HBsAg) in children under five years dropped from 4.7% before vaccination to 1.3% by 2015, thanks to universal vaccination.^{Go to footnote 3535, Go to footnote 3636, Go to footnote 3737} As of December 2025, 118 of 194 WHO Member States had introduced universal hepatitis B birth-dose vaccination, and 25 countries provided targeted birth-dose vaccination for infants born to HBV-positive mothers.^{Go to footnote 3838}

Although WHO has not set a formal global elimination target for invasive Hib disease, very low incidence is biologically and programmatically achievable where high and sustained Hib conjugate vaccine coverage is maintained. After the introduction of Hib conjugate vaccines, countries like the US, UK, and Canada documented a reduction in Hib disease incidence by over 95%, with near-elimination of invasive Hib disease in children under five years old in some high-coverage settings. More than 90% of countries have included Hib vaccines in their national immunization programs, resulting in substantial global decreases in Hib disease, where high and sustained Hib vaccine coverage is maintained.^{Go to footnote 3939, Go to footnote 4040, Go to footnote 4141}

Polio vaccination has reduced reported poliomyelitis cases by over 99.9% globally since the launch of the Global Polio Eradication Initiative in 1988. Coordinated immunization campaigns have led to the certification of polio-free status in the Americas (1994), the Western Pacific (2000), Europe (2002), South-East Asia Region (2014), and Africa (2020). Globally, the vaccines (Polio mono and multivalent and IPV-containing combination vaccines) have been central to progress towards wild polio eradication, with endemic wild poliovirus transmission remaining confined to Afghanistan and Pakistan. While the number of cases of WPV has declined and is mainly restricted to two endemic countries, there has been an increase in cases caused by cVDPV. An independent evaluation concluded that the overriding failure of the tOPV to-bOPV switch was the inability to close out outbreaks with timely, high-quality responses of an adequate scale.^{Go to footnote 4242} 

Achieving high coverage with routine poliovirus vaccine coverage and a timely and effective vaccine response to a surge in cases plays a critical role in controlling outbreaks of wild poliovirus and cVDPVs.^{Go to footnote 4343, Go to footnote 4444, Go to footnote 4545, Go to footnote 4646, Go to footnote 4747}