New and Underused Vaccines

Vaccine Surveillance & Introduction

The Expanded Program on Immunization (EPI) was established by the World Health Organization (WHO) in 1974 to provide protection against six vaccine-preventable diseases through routine infant immunization:

  • tuberculosis
  • poliomyelitis
  • diphtheria
  • tetanus
  • pertussis
  • measles

Since then, many new vaccines have become available and global public funding for immunization, including the Global Alliance for Vaccines and Immunisation (GAVI Alliance), has increased accessibility to these vaccines.

Most of the new or underused vaccines, including hepatitis B (HepB) vaccine, Haemophilus influenzae type b (Hib) vaccine, pneumococcal conjugate vaccine (PCV), rotavirus (RV) vaccine, and rubella-containing vaccine, are intended to be included in the routine childhood immunization schedule. Other new or underused vaccines, such as cholera vaccine, human papillomavirus (HPV) vaccine, meningococcal vaccine, yellow fever vaccine, and typhoid vaccine are intended for older or at-risk populations.


Electron Microscopy of the Cholera bacterium

Cholera is an acute, diarrheal illness caused by infection with the toxigenic bacterium Vibrio cholerae serogroups O1 and O139. The disease is transmitted through the fecal-oral route primarily through polluted water. Outbreaks occur most often in settings with poor water and sanitation infrastructure. An estimated 3 to 5 million cholera cases and more than 100,000 deaths occur each year around the world.

The infection is often mild or without symptoms, but can sometimes be severe. About 5% of infected persons will have severe disease characterized by excessive watery diarrhea, vomiting, and leg cramps. In these people, rapid loss of body fluids leads to dehydration and shock. Without treatment, death can occur within hours.

Rehydration treatment, provision of safe water, and adequate sanitation and hygiene remain the mainstay of cholera control and prevention efforts. Cholera vaccines are an additional tool until long-term improvements in water and sanitation infrastructure occur. Two oral cholera vaccines are currently available internationally:

  • Dukoral® (manufactured by Crucell/SBL Vaccine, Sweden), and
  • Shanchol™ (manufactured by Shantha Biotechnics/Sanofi, India)

Both vaccines are killed, whole-cell, two-dose vaccines.

CDC’s work related to cholera vaccines:

Additional Cholera Resources:

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Haemophilus Influenzae Type B (Hib)

Electron Microscopy of Haemophilus influenzae type b

Haemophilus influenzae type b (Hib) disease is a leading cause of childhood bacterial meningitis, pneumonia, and other serious infections. Hib vaccines are safe and work well even when given in early infancy. The vaccine is included in routine childhood vaccination programs in more than 184 countries in all regions of the world.

As a result, invasive Hib disease has been practically eliminated in many industrialized countries, and its incidence has been dramatically reduced in some parts of the developing world. WHO recommends the use of Hib vaccines in all routine infant immunization programs.

CDC’s work related to Hib vaccines:

  • Participate in post-introduction evaluations of Hib vaccination in Bosnia and Herzegovina, India, Nigeria, and Ukraine.
  • Strengthen disease surveillance and response in Central Africa – Le Projet de Renforcement de la Surveillance en Afrique Centrale (SURVAC).
  • Provide technical support for surveillance and evaluations of vaccine impact/effectiveness in several locations including Mongolia, Ukraine, Mozambique, Bangladesh, Pakistan, Chile, Colombia, Uruguay, Argentina, Eastern Mediterranean region.

Additional Hib Resources:

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Hepatitis B

Electron Microscopy of the Hepatitis B Virus

Hepatitis B is a liver disease caused by the hepatitis B virus (HBV). It ranges in severity from a mild illness, lasting a few weeks (acute), to a serious long-term (chronic) illness that can lead to cirrhosis or liver cancer.

HBV is transmitted by percutaneous (i.e., puncture through the skin) or mucosal (i.e., direct contact with mucous membranes) exposure with infectious blood and other body fluids. The major, global routes of transmission are from mother to infant (perinatal), child to child (non-sexual person to person contact), sexual contact, and percutaneous exposure to blood or other infectious body fluids.

The World Health Organization recommends hepatitis B vaccination for all infants beginning at birth, as part of the routine childhood vaccination schedule in all countries. Recommendations for catch-up vaccination of older age groups vary by country based on the epidemiology of each region’s infection and disease rates.

CDC’s work to prevent hepatitis B
CDC provides both scientific and technical support to partners and countries in other parts of the world to decrease the burden of hepatitis B infection.

Documenting the magnitude of the problem

  • Conduct surveys to evaluate the prevalence of hepatitis B among children in the Philippines, Papua New Guinea, Haiti, Solomon Islands, and Tajikistan
  • Conduct surveys to assess the burden of hepatitis B in pregnant women in Haiti to guide vaccination policy
  • Assess the burden of hepatitis B in Afghanistan to determine if birth dose of hepatitis B vaccine should be introduced
  • Assess the burden of mother-to-child transmission of hepatitis B in Africa to inform hepatitis B vaccine birth dose introduction


  • Assess whether or not hepatitis B can be detected through saliva (oral fluids)
  • Assessing whether or not rapid field testing methods are accurate compared to the gold standard ELISA lab-based testing

Improving coverage of hepatitis B vaccine birth dose

  • Pilot to evaluate best practices for using hepatitis B vaccine in a controlled temperature chain in rural Lao PDR, Papua New Guinea, and the Solomon Islands; plan to scale up in 2017-2019
  • Pilot to evaluate the impact of providing cell phones to village health volunteers to improve timely reporting of new home births and its impact on birth dose administration in Lao PDR
  • Evaluating and improving birth dose implementation in health facilities in Cambodia, Lao PDR, the Philippines, and Papua New Guinea
  • Evaluating selective hepatitis B birth dose vaccination in Sao Tome and Principe: a program assessment and cost-effectiveness study
  • Contribute to the Global hepatitis B birth dose introduction guidelines

Evaluating the impact of hepatitis B vaccines after introduction

  • Implement serosurveys in Bangladesh, Cambodia, the Philippines, South Pacific Islands (French Polynesia, Cook Islands, Tokelau, Tuvalu, Kiribati, Niue, Nauru), Papua New Guinea, and Oman to document the impact of hepatitis B vaccine and progress of countries to reach the hepatitis B control/elimination goal
  • Implement a two-stage survey to verify the achievement of hepatitis B elimination in Colombia
  • Assisting GAVI Alliance with estimating lives saved because of hepatitis B vaccine

Additional Hepatitis B Resources:

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Human Papillomavirus (HPV)

Electron Microscopy of human papillomavirus

Human papillomavirus (HPV) is the most common sexually transmitted infection (STI). There are more than 40 HPV types that can infect the genital areas of males and females. These HPV types can also infect the mouth and throat. HPV is passed through genital contact, most often during vaginal and anal sex. HPV may also be passed during oral sex and genital-to-genital contact between straight and same-sex partners—even when the infected person has no signs or symptoms. Most people with HPV never develop symptoms or health problems.

Most HPV infections (90%) resolve within two years. However, some HPV infections persist and can cause a variety of serious health problems, including:

  • cervical cancer,
  • genital warts,
  • recurrent respiratory papillomatosis (a rare condition in which warts grow in the throat), and
  • other types of genital and oropharyngeal cancers.

HPV is the main cause of cervical cancer in women. Each year, nearly 530,000 women contract cervical cancer and 275,000 die from it; a disproportionate number of these deaths occur in developing countries.

Currently, two HPV vaccines are available internationally – Cervarix (GlaxoSmithKline) and Gardasil (Merck). HPV vaccines are given as a series of three shots over 6 months. Both vaccines protect against cervical cancers caused by HPV types 16 and 18 in women. One vaccine, Gardasil, also protects against genital warts caused by HPV types 6 and 11, and has also been shown to prevent cancers of the anus, vagina, and vulva caused by HPV 16 and 18. Both vaccines are available for females. Gardasil is also available for males in some countries. HPV vaccines offer the best protection to girls and boys who receive all three vaccine doses and have time to develop an immune response before being sexually active with another person. WHO recommends HPV vaccination for girls 9 to 13 years old.

CDC’s work related to HPV vaccines:

Additional HPV Resources:

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Japanese Encephalitis

Carrier of Japanese Encephalitis

Japanese encephalitis (JE) virus is the leading vaccine-preventable cause of encephalitis in Asia, causing an estimated 67,900 cases yearly. JE is a mosquito-borne disease with a 20 to 30% case-fatality rate and neurologic or psychiatric sequelae in 30 to 50% of survivors.

Several types of JE vaccine are used globally. These include:

  • inactivated mouse brain–derived vaccine,
  • inactivated Vero cell culture-derived vaccines,
  • live attenuated vaccine based on the SA 14-14-2 JE virus strain, and
  • live attenuated chimeric vaccine.

CDC’s work related to JE vaccines:

  • Assist the Cambodian Ministry of Health to evaluate the impact on meningoencephalitis of a vaccination campaign using live attenuated SA 14-14-2 JE vaccine.
  • Provide technical assistance for JE surveillance to the International Center for Diarrhoeal Disease Research (ICDDR, b) and the Government of Bangladesh.

Additional Japanese Encephalitis Resources:

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Serogroup A Meningococcal Disease

Electron Microscopy of Meningitis-A

Since the introduction of H. influenzae type b (Hib) conjugate vaccines, N. meningitidis and S. pneumoniae have become the most common causes of bacterial meningitis in the world. N. meningitidis serogroup A causes large epidemics in developing countries, specifically in the countries of the African ‘meningitis belt.’

A meningococcal A (MenA) conjugate vaccine, intended for use mainly in the African ‘meningitis belt,’ was licensed in 2010. By the end of 2012, more than 100 million people in Africa had been vaccinated against serogroup A meningococcal disease.

CDC’s work related to serogroup A meningococcal vaccines:

Additional Serogroup A Meningococcal Disease Resources:

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Electron Microscopy of Streptococcus pneumoniae

Streptococcus pneumoniae is the bacterium responsible for pneumococcal disease, a leading cause of childhood pneumonia, meningitis, and sepsis. Worldwide, an estimated 14.5 million episodes of serious pneumococcal disease occur each year among children under 5 years of age, resulting in approximately 500,000 deaths, most of which occur in low and middle-income countries.

Pneumococcal conjugate vaccines (PCVs) can provide protection against pneumococcal disease. The World Health Organization recommends PCV be included in every country’s national immunization program, especially in countries with high pneumococcal disease burden.

CDC’s work related to pneumococcal vaccines:

  • Participate in post-introduction evaluation of pneumococcal conjugate vaccine in Ghana and Kenya.
  • Strengthen disease surveillance and response in Central Africa – Le Projet de Renforcement de la Surveillance en Afrique Centrale (SURVAC).
  • Technical support for surveillance and evaluations of pneumococcal conjugate vaccine impact/effectiveness in several locations including Haiti, Colombia, Brazil, Uruguay, Dominican Republic, South Africa, Mozambique, Malawi, Kenya, Burkina Faso, Bangladesh, and Pakistan.
  • CDC Streptococcal laboratory serves as the global reference laboratory for World Health Organization Invasive Bacterial Diseases Networkexternal icon

Additional Pneumococcus Resources:

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Electron microscopy of Rotavirus

Rotavirus is the leading cause of severe diarrhea among infants and young children worldwide. Before rotavirus vaccines were available, almost all children were infected with rotavirus, regardless of where they lived.

The World Health Organization recommends that rotavirus vaccine be included in every country’s national immunization program. Since 2006, more than 40 countries have introduced rotavirus vaccines into their national immunization programs. Many countries have since documented substantial declines in rotavirus disease burden in both vaccinated and unvaccinated children.

CDC’s work related to rotavirus vaccines:

  • Participate in post-introduction evaluations of rotavirus vaccine (past evaluations in Armenia, Ghana, Moldova, Rwanda, and Tanzania).
  • Conduct surveillance and vaccine impact evaluations in many countries including Armenia, Moldova, Bolivia, Brazil, Mexico, Nicaragua, Ghana, Malawi, Rwanda, and South Africa.
  • Strengthen disease surveillance and response in Central Africa – Le Projet de Renforcement de la Surveillance en Afrique Centrale (SURVAC).

Additional Rotavirus Resources:

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Electron Microscopy of rubella

Rubella is usually a mild, self-limited infection causing fever and rash in children and adults. Rubella’s public health importance is due to the potential of the virus to cause malformations of an embryo or fetus in infected pregnant women, especially during the first trimester of pregnancy. Infection can result in poor pregnancy outcomes, including miscarriage, fetal death, or infants born with congenital malformations, known as Congenital Rubella Syndrome (CRS). More than 100,000 infants with CRS are born each year. A safe and effective vaccine was introduced in 1969, but has not been introduced in all countries.CDC’s work related to rubella vaccines:

  • Provide expertise to WHO and other immunization partners to develop global policies to improve the control of rubella and prevent CRS.
  • Establish and strengthen CRS surveillance systems and sero-surveys to support countries collecting and analyzing the burden of rubella and CRS.
  • Conduct research, including modeling and economic studies.
  • Develop plans for
    • Introducing the rubella vaccine at the global, regional, and country levels,
    • monitoring the program,
    • establishing and strengthening both rubella and CRS surveillance systems,
    • documenting the elimination of the rubella/CRS, and
    • assisting in maintaining elimination.

Additional Rubella Resources:

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Electron Microscopy of the bacterium s. typhi.

Typhoid fever (typhoid) is a severe, systemic infection caused by the bacterium Salmonella Typhi (S. Typhi). It causes an estimated 21 million cases and 216,000 to 600,000 deaths worldwide each year. The infection is transmitted through the fecal-oral route from acutely infected individuals or from recovering or chronic carriers. The majority of typhoid cases and deaths occur among populations that lack access to drinkable water, adequate sanitation, and hygienic facilities – primarily in south Asia and sub-Saharan Africa.

Typhoid is clinically difficult to tell apart from many other illness caused by fever, including paratyphoid fever, dengue, malaria, and leptospirosis, which may also be widespread or cause epidemics in the same geographic areas.

Ensuring safe water, adequate sanitation, and improved hygiene are the definitive measures for typhoid fever prevention and control. Typhoid vaccines are an additional complementary tool. The WHO recommends use of typhoid fever vaccination in endemic areas and for outbreak control. Two typhoid vaccines are licensed and available in many countries:

  • the Ty21a vaccine, which is an oral, live, attenuated vaccine, and
  • the Vi polysaccharide vaccine, which is a subunit, injectable, single dose vaccine and is licensed for persons 2 years and older.

Several newer typhoid conjugate vaccines, which can be incorporated into the routine infant immunization schedule, are in different stages of development. One has recently been launched in India.

CDC’s work related to typhoid vaccines:

  • Active member of the Coalition Against Typhoid.
  • Evaluation of the impact of a mass typhoid fever vaccination campaign, Fiji 2011.
  • Investigate typhoid fever outbreak and response in several countries, including Malawi, Uganda, Zambia, and Zimbabwe.
  • Conduct initial studies of vaccine acceptability in Malawi and Uganda.
  • Technically assist countries with laboratory services and trainings for blood culture and rapid typhoid detection tests.
  • Serve as co-investigators for the multi-country project – Typhoid fever surveillance in Africa (TSAP).

Additional Typhoid Resources:

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Yellow Fever

Photo of a yellow fever carrier

Yellow fever is a mosquito-borne disease that is endemic to sub-Saharan Africa and tropical South America. Yellow fever virus is estimated to cause 200,000 cases of disease and 30,000 deaths each year, with 90% occurring in Africa.

Yellow fever varies from a mild, undifferentiated illness with fever, to severe disease with jaundice and hemorrhage or severe bleeding. Twenty to 50% of persons with the severe disease die.

All currently available yellow fever vaccines are live-attenuated vaccines that use the 17D strain. Studies comparing the various vaccines show no difference in the side effects or immune responses generated by these vaccines.

CDC’s work related to yellow fever vaccines:

  • Help the World Health Organization assess yellow fever virus activity in selected African countries and implement protocols related to yellow fever vaccine immunity and safety.
  • Provide technical assistance to the GAVI-sponsored Yellow Fever Initiative that aims to reduce the risk of yellow fever epidemics by improving vaccination coverage in higher risk countries.

Additional Yellow Fever Resources:

Page last reviewed: July 20, 2017
Content source: Global Immunization