Vaccination of travelers: how far have we come and where are we going?

Hepatitis B vaccination coverage among adults aged ≥18 years traveling to a country of high or intermediate endemicity, United States, 2015

BACKGROUND

Persons from the United States who travel to developing countries are at substantial risk for hepatitis B virus (HBV) infection. Hepatitis B vaccine has been recommended for adults at increased risk for infection, including travelers to high or intermediate hepatitis B endemic countries.

PURPOSE

To assess hepatitis B vaccination coverage among adults ≥18 years traveling to a country of high or intermediate endemicity from the United States.

METHODS

Data from the 2015 National Health Interview Survey (NHIS) were analyzed to determine hepatitis B vaccination coverage (≥1 dose) and series completion (≥3 doses) among persons aged ≥18 years who reported traveling to a country of high or intermediate hepatitis B endemicity. Multivariable logistic regression and predictive marginal analyses were conducted to identify factors independently associated with hepatitis B vaccination.

RESULTS

In 2015, hepatitis B vaccination coverage (≥1 dose) among adults aged ≥18 years who reported traveling to high or intermediate hepatitis B endemic countries was 38.6%, significantly higher compared with 25.9% among non-travelers. Series completion (≥3 doses) was 31.7% and 21.2%, respectively (P < 0.05). On multivariable analysis among all respondents, travel status was significantly associated with hepatitis B vaccination coverage and series completion. Other characteristics independently associated with vaccination (≥1 dose, and ≥3 doses) among travelers included age, race/ethnicity, educational level, duration of US residence, number of physician contacts in the past year, status of ever being tested for HIV, and healthcare personnel status.

CONCLUSIONS

Although travel to a country of high or intermediate hepatitis B endemicity was associated with higher likelihood of hepatitis B vaccination, hepatitis B vaccination coverage was low among adult travelers to these areas. Healthcare providers should ask their patients about travel plans and recommend and offer travel related vaccinations to their patients or refer them to alternate sites for vaccination.

Hepatitis B vaccination coverage among adults aged ≥ 18 years traveling to a country of high or intermediate endemicity, United States, 2015

BACKGROUND

Persons from the United States who travel to developing countries are at substantial risk for hepatitis B virus (HBV) infection. Hepatitis B vaccine has been recommended for adults at increased risk for infection, including travelers to high or intermediate hepatitis B endemic countries.

PURPOSE

To assess hepatitis B vaccination coverage among adults ≥ 18 years traveling to a country of high or intermediate endemicity from the United States.

METHODS

Data from the 2015 National Health Interview Survey (NHIS) were analyzed to determine hepatitis B vaccination coverage (≥1 dose) and series completion (≥3 doses) among persons aged ≥ 18 years who reported traveling to a country of high or intermediate hepatitis B endemicity. Multivariable logistic regression and predictive marginal analyses were conducted to identify factors independently associated with hepatitis B vaccination.

RESULTS

In 2015, hepatitis B vaccination coverage (≥1 dose) among adults aged ≥ 18 years who reported traveling to high or intermediate hepatitis B endemic countries was 38.6%, significantly higher compared with 25.9% among non-travelers. Series completion (≥3 doses) was 31.7% and 21.2%, respectively (P < 0.05). On multivariable analysis among all respondents, travel status was significantly associated with hepatitis B vaccination coverage and series completion. Other characteristics independently associated with vaccination (≥1 dose, and ≥ 3 doses) among travelers included age, race/ethnicity, educational level, duration of U.S. residence, number of physician contacts in the past year, status of ever being tested for HIV, and healthcare personnel status.

CONCLUSIONS

Although travel to a country of high or intermediate hepatitis B endemicity was associated with higher likelihood of hepatitis B vaccination, hepatitis B vaccination coverage was low among adult travelers to these areas. Healthcare providers should ask their patients about travel plans and recommend and offer travel related vaccinations to their patients or refer them to alternate sites for vaccination.

Prospects for dengue vaccines for travelers

Travel-acquired dengue cases have been increasing as the overall global dengue burden has expanded. In Korea, imported dengue cases have been reported since 2000 when it first became a notifiable disease. During the first four months of 2016, three times more dengue cases were reported in Korea than during the same period the previous year. A safe and efficacious vaccine for travelers would be beneficial to prevent dengue disease in individual travelers and potentially decrease the risk of virus spread to non-endemic areas. Here, we summarize the characteristics of dengue vaccines for travelers and review dengue vaccines currently licensed or in clinical development.

An overview of travel-associated central nervous system infectious diseases: risk assessment, general considerations and future directions

Nervous system infections are among the most important diseases in travellers. Healthy travellers might be exposed to infectious agents of central nervous system, which may require in-patient care. Progressive course is not uncommon in this family of disorders and requires swift diagnosis. An overview of the available evidence in the field is, therefore, urgent to pave the way to increase the awareness of travel-medicine practitioners and highlights dark areas for future research. In November 2013, data were collected from PubMed, Scopus, and Web of Knowledge (1980 to 2013) including books, reviews, and peer-reviewed literature. Works pertained to pre-travel care, interventions, vaccinations related neurological infections were retrieved. Here we provide information on pre-travel care, vaccination, chronic nervous system disorders, and post-travel complications. Recommendations with regard to knowledge gaps, and state-of-the-art research are made. Given an increasing number of international travellers, novel dynamic ways are available for physicians to monitor spread of central nervous system infections. Newer research has made great progresses in developing newer medications, detecting the spread of infections and the public awareness. Despite an ongoing scientific discussion in the field of travel medicine, further research is required for vaccine development, state-of-the-art laboratory tests, and genetic engineering of vectors.

Business travelers: vaccination considerations for this population

Illness in business travelers is associated with reduced productivity on the part of the employee as well as the employer. Immunizations offer a reliable method of preventing infectious diseases for international business travelers. The authors review the travel patterns of business travelers, available data on illnesses they encounter, their potential travel-associated risks for vaccine-preventable diseases and recommendations on immunizations for this population. Routine vaccines (e.g., measles, tetanus and influenza) should be reviewed to assure that they provide current coverage. The combined hepatitis A and hepatitis B vaccine with a rapid schedule offers options for those with time constraints. Other vaccine recommendations for business travelers need to focus on their destinations and activities and underlying health, taking into account the concept of cumulative risk for those with frequent travel, multiple trips or long stays.

Hepatitis A vaccination coverage among adults 18-49 years traveling to a country of high or intermediate endemicity, United States

BACKGROUND

Since 1996, hepatitis A vaccine (HepA) has been recommended for adults at increased risk for infection including travelers to high or intermediate hepatitis A endemic countries. In 2009, travel outside the United States and Canada was the most common exposure nationally reported for persons with hepatitis A virus (HAV) infection.

OBJECTIVE

To assess HepA vaccination coverage among adults 18-49 years traveling to a country of high or intermediate endemicity in the United States.

METHODS

We analyzed data from the 2010 National Health Interview Survey (NHIS), to determine self-reported HepA vaccination coverage (≥1 dose) and series completion (≥2 dose) among persons 18-49 years who traveled, since 1995, to a country of high or intermediate HAV endemicity. Multivariable logistic regression and predictive marginal analyses were conducted to identify factors independently associated with HepA vaccine receipt.

RESULTS

In 2010, approximately 36.6% of adults 18-49 years reported traveling to high or intermediate hepatitis A endemic countries; among this group unadjusted HepA vaccination coverage was 26.6% compared to 12.7% among non-travelers (P-values<0.001) and series completion were 16.9% and 7.6%, respectively (P-values<0.001). On multivariable analysis among all respondents, travel status was an independent predictor of HepA coverage and series completion (both P-values<0.001). Among travelers, HepA coverage and series completion (≥2 doses) were higher for travelers 18-25 years (prevalence ratios 2.3, 2.8, respectively, P-values<0.001) and for travelers 26-39 years (prevalence ratios 1.5, 1.5, respectively, P-value<0.001, P-value=0.002, respectively) compared to travelers 40-49 years. Other characteristics independently associated with a higher likelihood of HepA receipt among travelers included Asian race/ethnicity, male sex, never having been married, having a high school or higher education, living in the western United States, having greater number of physician contacts or receipt of influenza vaccination in the previous year. HepB vaccination was excluded from the model because of the significant correlation between receipt of HepA vaccination and HepB vaccination could distort the model.

CONCLUSIONS

Although travel to a country of high or intermediate hepatitis A endemicity was associated with higher likelihood of HepA vaccination in 2010 among adults 18-49 years, self-reported HepA vaccination coverage was low among adult travelers to these areas. Healthcare providers should ask their patients' upcoming travel plans and recommend and offer travel related vaccinations to their patients.

Vaccine-preventable diseases and their prophylaxis

Global uptake of new vaccines shapes the epidemiology of infections, and in turn this changing epidemiology guides vaccine development. Once introduced, surveillance and monitoring of the impact of vaccines on disease and adverse events is vital for further development. This article reviews the use of vaccines as part of routine health care, vaccines that may be required for entry into a destination country, and vaccines that are recommended because of risk during travel. Considerations and advances in the vaccination of travelers are addressed.