Immunization and AEFI

Adverse Events Following Immunization (AEFI) are medical events that occur after a person receives a vaccine, which may or may not be related to the vaccine itself. These events can range from mild reactions, such as soreness or fever, to more severe outcomes like allergic reactions or neurological complications. The causality assessment process is vital in determining whether the vaccine directly caused the event or if it was coincidental. This involves a detailed investigation of the case, gathering clinical, laboratory, and epidemiological data, followed by classifying the event into categories like vaccine product-related, immunization error-related, or coincidental. Medical experts then review the evidence to assess the likelihood of a causal relationship. A proper case investigation is critical to distinguish true vaccine-related risks from unrelated health incidents, helping to maintain public confidence in vaccination programs. By ensuring accurate assessments, causality evaluation supports vaccine safety monitoring, helps address concerns, and strengthens the overall immunization system.incidents, ensuring public trust in vaccines and supporting overall immunization safety.

A Verbal Autopsy (VA) is a method used to determine probable causes of death in cases where no formal medical record or death certificate is available. In the context of Adverse Events Following Immunization (AEFI), a verbal autopsy involves interviewing family members or caregivers about the symptoms and circumstances leading to the individual's death. This process helps health authorities to assess whether the death could be linked to the vaccination or other unrelated causes. It is especially useful in resource-limited settings where medical infrastructure might not capture every detail of mortality cases.

An Adverse Event Following Immunization (AEFI) investigation into a death after vaccination aims to determine whether the death was related to the vaccine or caused by other factors. The process begins with the initial reporting of the death, followed by comprehensive data collection, including medical history, vaccination details, and clinical symptoms. A multidisciplinary team analyzes this data to assess the temporal relationship between the vaccination and death, using standardized criteria to determine if the death was due to the vaccine, a quality defect, immunization error, anxiety, or a coincidental cause. Findings are then communicated to public health authorities, manufacturers, and the public to ensure transparency and maintain trust. If a link is found, corrective actions, such as recalling a vaccine batch or revising guidelines, may be taken. All findings are documented for future reference and to improve vaccine safety monitoring and public health responses.

Conducting a post-mortem examination in cases where vaccination is suspected to have contributed to death requires a meticulous and systematic approach to uncover relevant evidence. Such examinations aim to determine if there is a causal link between the vaccination and the observed adverse events leading to death. This process involves a comprehensive review of medical records, careful external and internal examinations, and precise documentation of findings. By adhering to standardized protocols and considering both medical and legal implications, pathologists can provide critical insights into the circumstances surrounding these rare but important events.

AEFI surveillance is essential for monitoring the safety of vaccines post-licensure. It involves systematic monitoring, reporting, and investigation of adverse events following immunization, ranging from mild local reactions to rare serious events. By collecting and analyzing data from healthcare providers and the public, health authorities can detect potential safety signals promptly. Causality assessments are conducted to determine the relationship between adverse events and vaccines, ensuring accurate risk-benefit evaluations. Effective surveillance systems contribute to maintaining public trust in immunization programs by providing timely information and ensuring the continued safety of vaccines in real-world settings.

: Expanded Programme on Immunization was launched in 1978. It was renamed as Universal Immunization Programme in 1985 when its reach was expanded beyond urban areas. In 1992, it became part of the Child Survival and Safe Motherhood Programme and in 1997 it was included in the ambit of the National Reproductive and Child Health Programme. Since the launch of the National Rural Health Mission in 2005, Universal Immunization Programme has always been an integral part of it. Knowledge regarding immunization will expand the base of work of health workers in the immunization process. This course is designed for Health care team members in the primary health care institutions to acquire in-depth knowledge regarding immunization programs, maintenance of cold chains, and AEFI.

Immunization, also known as vaccination, is a crucial public health intervention aimed at preventing and controlling the spread of infectious diseases. It involves administering vaccines to individuals to stimulate their immune system, helping them develop immunity against specific pathogens such as bacteria or viruses. Immunization is a cost-effective and efficient way to protect individuals and communities from various infectious diseases. AEFI refers to any untoward medical occurrence that follows immunization, but which does not necessarily have a causal relationship with the vaccine. AEFI can include local reactions at the injection site, systemic reactions, and rare, serious events. In summary, immunization is a cornerstone of public health, preventing the spread of infectious diseases. AEFI surveillance ensures the ongoing safety of vaccination programs by promptly identifying and addressing any adverse events, thus contributing to maintaining public confidence in immunization.