Implementing Serosurveys in India: Experiences, Lessons Learned, and Recommendations.

Serological surveillance for vaccine-preventable diseases, such as measles and rubella, can provide direct measures of population immunity across age groups, identify gaps in immunity, and document changes in immunity over time. Rigorously conducted, representative household serosurveys provide high-quality estimates with minimal bias. However, they can be logistically challenging, expensive, and have higher refusal rates than vaccine coverage surveys. This article shares lessons learned through implementing nine measles and rubella household serosurveys in five districts in India-the challenges faced, the potential impact on results, and recommendations to facilitate the conduct of serosurveys. Specific lessons learned arose from challenges related to community mobilization owing to lack of cooperation in certain settings and populations, limitations of outdated census information, nonresponse due to refusal or unavailability during survey enumeration and enrollment, data collection issues, and specimen collection and handling issues. Although some experiences are specific to serosurveys in India, these lessons are generalizable to other household surveys, particularly vaccination coverage and serosurveys conducted in low- and middle-income settings.

Infections in immunosuppressed travellers with autoimmune inflammatory diseases-a narrative review and advice for clinical practice.

The management of autoimmune, inflammatory diseases has been revolutionized by biologic therapies. A beneficial consequence of better disease control is that more patients are well enough to travel the world. There is now a class of traveller, the significantly immunosuppressed person with autoimmune disease, with specific risks and requirements. This review introduces the concept of the pre-travel risk assessment and discusses the major vaccine-preventable and non-vaccine-preventable travel-associated infections. The challenges and controversies around vaccination and immunosuppression are reviewed with advice for clinical practice.

Addressing Parental Vaccine Hesitancy and Other Barriers to Childhood/Adolescent Vaccination Uptake During the Coronavirus (COVID-19) Pandemic.

Routine childhood immunizations are proven to be one of the most effective public health interventions at controlling numerous deadly diseases. Therefore, the CDC recommends routine immunizations for children and adolescent populations against vaccine-preventable diseases e.g., tetanus, pertussis, diphtheria, etc. This current review sought to examine barriers to pediatric vaccine uptake behaviors during the COVID-19 pandemic. We also explored the implications for parental vaccine hesitancy/delay during an ongoing health crisis and proposed recommendations for increasing vaccine confidence and compliance. Our review determined that the receipt for vaccinations steadily improved in the last decade for both the United States and Tennessee. However, this incremental progress has been forestalled by the COVID-19 pandemic and other barriers i.e. parental vaccine hesitancy, social determinants of health (SDoH) inequalities, etc. which further exacerbate vaccination disparities. Moreover, non-compliance to routine vaccinations could cause an outbreak of diseases, thereby, worsening the ongoing health crisis and already strained health care system. Healthcare providers are uniquely positioned to offer effective recommendations with presumptive languaging to increase vaccination rates, as well as, address parental vaccine hesitancy. Best practices that incorporate healthcare providers' quality improvement coaching, vaccination reminder recall systems, adherence to standardized safety protocols (physical distancing, hand hygiene practices, etc.), as well as, offer telehealth and outdoor/drive-through/curbside vaccination services, etc. are warranted. Additionally, a concerted effort should be made to utilize public health surveillance systems to collect, analyze, and interpret data, thereby, ensuring the dissemination of timely, accurate health information for effective health policy decision-making e.g., vaccine distribution, etc.

Antibodies against vaccine-preventable infections after CAR-T cell therapy for B cell malignancies.

BACKGROUNDLittle is known about pathogen-specific humoral immunity after chimeric antigen receptor-modified T (CAR-T) cell therapy for B cell malignancies.METHODSWe conducted a prospective cross-sectional study of CD19-targeted or B cell maturation antigen-targeted (BCMA-targeted) CAR-T cell therapy recipients at least 6 months posttreatment and in remission. We measured pathogen-specific IgG against 12 vaccine-preventable infections and the number of viral and bacterial epitopes to which IgG was detected ("epitope hits") using a serological profiling assay. The primary outcome was the proportion of participants with IgG levels above a threshold correlated with seroprotection for vaccine-preventable infections.RESULTSWe enrolled 65 children and adults a median of 20 months after CD19- (n = 54) or BCMA- (n = 11) CAR-T cell therapy. Among 30 adults without IgG replacement therapy (IGRT) in the prior 16 weeks, 27 (90%) had hypogammaglobulinemia. These individuals had seroprotection to a median of 67% (IQR, 59%-73%) of tested infections. Proportions of participants with seroprotection per pathogen were comparable to population-based studies, but most individuals lacked seroprotection to specific pathogens. Compared with CD19-CAR-T cell recipients, BCMA-CAR-T cell recipients were half as likely to have seroprotection (prevalence ratio, 0.47; 95% CI, 0.18-1.25) and had fewer pathogen-specific epitope hits (mean difference, -90 epitope hits; 95% CI, -157 to -22).CONCLUSIONSeroprotection for vaccine-preventable infections in adult CD19-CAR-T cell recipients was comparable to the general population. BCMA-CAR-T cell recipients had fewer pathogen-specific antibodies. Deficits in both groups support the need for vaccine and immunoglobulin replacement therapy studies.FUNDINGSwiss National Science Foundation (Early Postdoc Mobility grant P2BSP3_188162), NIH/National Cancer Institute (NIH/NCI) (U01CA247548 and P01CA018029), NIH/NCI Cancer Center Support Grants (P30CA0087-48 and P30CA015704-44), American Society for Transplantation and Cellular Therapy, and Juno Therapeutics/BMS.

COVID-19 outbreak: a potential threat to routine vaccination programme activities in Nigeria.

COVID-19 is an infectious disease caused by the most recently discovered coronavirus (SARS-CoV-2). The virus and disease were unknown before the outbreak began in the city of Wuhan, China, in December 2019. Nigeria and other sub-Sahara Africa countries like the rest of the world introduced several lockdown measures as part of their public health response to mitigate the spread of the virus. This, however, was not without the likelihood of consequences considering the weak health systems. The access and supply side of vaccination was more likely to have been affected by the lockdown measures. When vaccination services are disrupted even for brief periods during emergencies, the risk of outbreak-prone vaccine-preventable diseases increases, leading to excess morbidity and mortality. This highlights the importance of maintaining essential services such as vaccination in times of emergency. There is therefore an urgent need to ensure that children are protected against those diseases for which vaccines already exist. The COVID-19 outbreak has posed a new hindrance to vaccination activities in Nigeria and across Sub-Saharan Africa with associated threat to surveillance of vaccine-preventable diseases. Achieving and sustaining high levels of vaccination coverage during this period must, therefore, be a priority for all health systems.

Principles of immunisation in children with solid organ transplant.

Vaccine-preventable diseases (VPD) are a significant risk to paediatric solid organ transplant (SOT) recipients on lifelong immunosuppressive therapy. Children progressing to end-stage organ dysfunction are unable to mount a robust immune response. Hence, it is important to plan vaccination early in the course of disease, especially if a child is anticipated to be a SOT candidate. Vaccine recommendations need to be individualised in this population based on vaccine history and serology. Catch-up or accelerated schedules may be used to complete vaccinations before transplant. Post-transplant, immunisation is recommenced in consultation with the transplant team taking into context the time since transplant and the intensity of the immunosuppressive regime. Inactivated vaccines are safe post-transplant but postexposure prophylaxis may still be required in children with inadequate immunity to VPD. Specific vaccines may be advised for SOT recipients travelling abroad (in consultation with a travel clinic) or those entering high-risk professions. Additionally, the vaccination status of all household members and close contacts should be reviewed and optimised, offering additional protection to the transplant recipient.

Impact of social distancing on incidence of vaccine-preventable diseases, South Korea.

While vaccination remains the cornerstone of controlling vaccine-preventive diseases (VPD), little is known about the effect of social distancing on incidence of VPDs. We investigated the impact of social distancing practiced during the coronavirus disease 2019 (COVID-19) pandemic on the incidence of selected VPDs in South Korea. National surveillance data on monthly incidence of hepatitis A, hepatitis B, varicella, mumps, invasive pneumococcal disease (IPD), and pertussis were retrieved and compared the VPD incidences in 2020 to the average of the last 4 years (2015-2019) of the corresponding months. In 2020, there were 44% decline for mumps, 44% decline for varicella, 28% decline for pertussis, 22% decline for IPD, 14% decline in incidence of hepatitis A, and no change for hepatitis B incidences, compared to baseline years (2015-2019). The largest decline of total VPDs was in April (65%) and in May (67%), during the intensified social distancing measures. In the setting of sustained vaccination coverage, social distancing may provide additional public health benefit in controlling the VPDs.

Immune surveillance for vaccine-preventable diseases.

INTRODUCTION: Immunesurveillance is an important tool to monitor the protection of the population against vaccine-preventable diseases, which is currently mostly based on the detection of specific serum antibodies. However, the landscape of immune surveillance is changing, driven by emerging and evolving pathogens, changes in the age distribution of the population and scientific understanding of protective immunity, necessitating a comprehensive review. AREAS COVERED: To anticipate these changes, reliable and high-throughput detection of antibody levels is desired to enable screening in larger population settings. Antibody levels alone do not always equate with protection and may require additional functional testing of the antibodies or immune cell-based assays. In addition, the location (systemic or locally mucosal) of the infection and whether the antibodies are induced through infection or vaccination have implications for both immune protection and assessing immune status. EXPERT COMMENTARY: In order to perform multicenter studies on many samples for multiple antigens, more validated reference materials and wider adoption of high-throughput techniques are needed. The field of serosurveillance will also benefit from better correlates of protection and understanding of (local) mechanisms of protection. Here we give an overview of the current state-of-the-art of serosurveillance and how the field could move forward.

Under-immunization of pediatric transplant recipients: a call to action for the pediatric community.

Vaccine-preventable infections (VPIs) are a common and serious complication following transplantation. One in six pediatric solid organ transplant recipients is hospitalized with a VPI in the first 5 years following transplant and these hospitalizations result in significant morbidity, mortality, graft injury, and cost. Immunizations are a minimally invasive, cost-effective approach to reducing the incidence of VPIs. Despite published recommendations for transplant candidates to receive all age-appropriate immunizations, under-immunization remains a significant problem, with the majority of transplant recipients not up-to-date on age-appropriate immunizations at the time of transplant. This is extremely concerning as the rate for non-medical vaccine exemptions in the United States (US) is increasing, decreasing the reliability of herd immunity to protect patients undergoing transplant from VPIs. There is an urgent need to better understand barriers to vaccinating this population of high-risk children and to develop effective interventions to overcome these barriers and improve immunization rates. Strengthened national policies requiring complete age-appropriate immunization for non-emergent transplant candidates, along with improved multi-disciplinary immunization practices and tools to facilitate and ensure complete immunization delivery to this high-risk population, are needed to ensure that we do everything possible to prevent infectious complications in pediatric transplant recipients.

Vaccination coverage and immunity levels against vaccine-preventable diseases in male Air Force recruits in Greece.

AIM: Data about susceptibility rates in young adults are scarce. We estimated the complete vaccination rates, timeliness of vaccinations and susceptibility rates among male military recruits in Greece. METHODS: A standardized form was used to collect data. Immunity against measles, rubella, varicella, hepatitis A and hepatitis B was serologically estimated. RESULTS: We studied 385 recruits with a mean age of 23.5 years (range: 18.3-29.9 years). Complete vaccination rates were 94.3% for measles, 100% for rubella, 15% for varicella, 73.9% for hepatitis A and 96.5% for hepatitis B. Only 10.8% of participants were fully vaccinated against all five diseases. Timely vaccination was 47.2% for measles, 89.3% for rubella and 48.1% for hepatitis B. Recruits >23 years had a 1.5-fold increased probability for incomplete vaccinations compared to younger recruits. Laboratory-confirmed immunity rates were 80% against measles, 85.7% against rubella, 85.2% against varicella, 69.4% against hepatitis A and 77.1% against hepatitis B. It is estimated that approximately 388,696 persons aged 18-30 years are susceptible to measles, 277,640 persons to rubella, 287,736 persons to varicella, 595,664 persons to hepatitis A and 444,224 persons to hepatitis B in Greece. CONCLUSION: Our study showed that young adults have significant immunity gaps against measles, rubella, varicella, hepatitis A and hepatitis B. Complete vaccination rates were suboptimal against hepatitis A and varicella. Strategies to access young adults and increase immunity rates through catch-up vaccination services should be investigated. A third dose of MMR vaccine should be considered for young adolescents in Greece.

Travel vaccination recommendations and infection risk in HIV-positive travellers.

BACKGROUND: With the advent of highly active antiretroviral drugs for the treatment of human immunodeficiency virus (HIV) it has become possible for people with HIV to travel to destinations that may place them at risk of a number of infectious diseases. Prevention of infections by vaccination is therefore of paramount importance for these travellers. However, vaccine responsiveness in HIV-positive individuals is not infrequently reduced compared to HIV-negative individuals. An understanding of the expected immune responses to vaccines in HIV-positive travellers is therefore important in planning the best approach to a pretravel consultation. METHODS: A PubMed search was performed on HIV or acquired immune deficiency syndrome together with a search for specific vaccines. Review of the literature was performed to develop recommendations on vaccinations for HIV-positive travellers to high-risk destinations. RESULTS: The immune responses to several vaccines are reduced in HIV-positive people. In the case of vaccines for hepatitis A, hepatitis B, influenza, pneumococcus, meningococcus and yellow fever there is a good body of data in the literature showing reduced immune responsiveness and also to help guide appropriate vaccination strategies. For other vaccines like Japanese encephalitis, rabies, typhoid fever, polio and cholera the data are not as robust; however, it is still possible to gain some understanding of the reduced responses seen with these vaccines. CONCLUSION: This review provides a summary of the immunological responses to commonly used vaccines for the HIV-positive travellers. This information will help guide travel medicine practitioners in making decisions about vaccination and boosting of travellers with HIV.

Vaccination Status in Pediatric Solid-Organ Transplant Recipients and Their Household Members.

OBJECTIVES: Vaccine-preventable diseases remain a major cause of morbidity and mortality in solid-organ transplant candidates and recipients. Newer recommendations include vaccination of all household members to create a herd immunity around the transplant recipient. This study evaluated the vaccination status of pediatric solid-organ transplant recipients and their household members. MATERIALS AND METHODS: We evaluated 30 pediatric solid-organ transplant recipients (14 kidney, 13 liver, 3 heart) and their household members (26 siblings, 30 parents) at time of transplant. RESULTS: Fourteen recipients (47%) received scheduled vaccinations before solid-organ transplant and were up to date for their age with their diphtheria, tetanus, pertussis; hepatitis B virus; poliomyelitis; Haemophilus influenzae type B; Streptococcus pneumoniae conjugate vaccine; and measles, mumps, and rubella vaccinations. Another 7 recipients (23%) had partially completed their schedules, only missing the second dose of the measles, mumps, and rubella vaccine. Fifteen siblings (58%) had either completed (n = 13, 50%) or partially completed (n = 2, 8%) their vaccinations. All 30 parents were either unaware of their vaccination status (n = 10, 33%) or had only incomplete vaccination records (n = 20, 67%). CONCLUSIONS: We found that most pediatric solid-organ transplant recipients to be appropriately vaccinated. However, vaccination status in household members, especially in parents, was disappointing.