One of the greatest public health achievements in history is the advent of vaccines. Vaccination against a variety of bacterial and viral diseases is a critical component of communicable disease prevention and control around the world. Vaccination against a particular disease decreases not only the disease’s prevalence but also the disease’s social and economic burden on communities. Some of the vaccine-preventable diseases are measles, whooping cough, flu, polio, pneumococcal disease, tetanus, Meningococcal disease, Hepatitis B, mumps, HIB, etc. Many vaccine-preventable diseases can be completely blocked by having a high immunization coverage. The global eradication of smallpox and the near-eradication of polio in many countries are outstanding examples of immunization’s role in disease control.

Despite these achievements, certain vaccine-preventable diseases appear to be resurfacing. Measles and mumps outbreaks, for example, have recently dominated the news. While the causes of disease resurgences are often complex and difficult to pinpoint, here are a few important reasons for some of these resurgences.

Anti-vaccination Movements

Social media has played an important role in spreading the vaccination fear among the educated masses. The spread of anti-vaccine news has led to many populations preventing their child from immunizations. One of the main reasons for fear of vaccination is the AEFI (Adverse Events Following Immunization). Few vaccines may cause some unfavorable side effects, which are usually minor, resolve rapidly, and can be effectively managed with adequate prior education and simple fever and pain medications. The majority of events attributed to vaccine administration are actually unrelated to the vaccine; many are unrelated to the vaccine, while others (particularly in developing countries) are due to human, or program, error. One of the most widely held misconceptions about vaccination is that it causes autism. The measles, mumps, and rubella (MMR) vaccine were linked to autism in British children, according to a British medical journal. The paper was later discredited due to many errors and false data. 

Waning Immunity

When given for the first time, pertussis vaccines are about 80% to 90% effective. After two doses, mumps vaccines are about 88 percent effective. However, research suggests that immunity fades over time and that more doses may be required to protect against outbreaks. The revival of measles isn’t the only vaccine-preventable disease. Pertussis and mumps cases have also been on the rise, and while vaccine refusal is undoubtedly a factor, another factor may be inadequate or waning immunity.

Climate Change 

Perhaps the most significant disease revival is yet to come. Extreme weather events, which have always posed a threat to human health and safety, are becoming more common as global temperatures rise, causing changes in not only the climate but also animal habitats and human interaction. Scientists warn that a warmer, wetter world would result in the revival of a variety of diseases. Heavy rains and associated flooding, for example, can overburden drains and clog sewer lines, contaminating water supplies and causing disease outbreaks such as cholera.  Warmer temperatures and more precipitation are causing tropical mosquito populations to migrate closer to the poles, posing a threat of an increase in vector-borne diseases like malaria. 9 Moreover, rising sea levels will inevitably displace entire communities, forcing them to relocate to increasingly urban areas, where diseases can spread more easily.

Coronavirus Pandemic

Suspension of vaccination drives due to the coronavirus pandemic can boost the reemergence of vaccine-preventable diseases in many countries and eventually their spread all around. In many countries, mass vaccination campaigns against a variety of diseases have already come to a halt. For many children, these vaccination efforts are their only opportunity to receive vaccines. Since the suspensions started, 13.5 million people have missed out on vaccines for polio, measles, HPV, yellow fever, cholera, and meningitis.

Vaccines are one of medicine’s most powerful fortresses. Life was difficult and brutal for children and adults before vaccines, according to history, and the number of deaths and diseases that vaccines have prevented cannot be underestimated. As a result, it is critical that the government and healthcare organizations make significant efforts to resume vaccination campaigns and work toward the eradication of vaccine-preventable diseases.