Risk of declining vaccine-induced immunity stress to measles, diphtheria and pertussis in children under exposure to airborne metals and aromatic hydrocarbons

Vaccine-induced immunity stress is largely determined by safety of the environment. The aim of this study was to estimate vaccine-induced immunity stress to measles, diphtheria and pertussis in children under airborne exposures and its relationship with levels of metals and aromatic hydrocarbons in patients’ blood.

The observation group was made of 417 children aged 6–17 years who lived in an area with ambient Mn, Cr, Ni and benzene levels equal to 1.0–13.8 average annual MPLs. The reference group included 196 children who lived in a tentatively safe area. The children were selected using the following criteria: completed vaccination / re-vaccination against preventable infections; living for more than 3 years in a selected area; absence of any disease in its decompensation state or ARVI; provided informed consent to participation. Chemical-analytical tests to identify levels of chemicals in blood were conducted in conformity with the valid methodical guidelines. Levels of vaccine-induced antibodies were identified by ELISA tests with their results interpreted in accordance with the requirements provided with employed test-systems.

The study established health risks in the area where the observation group lived; if expressed through hazard indexes, they amounted to 4.3 (alerting risk) for the immune system and 6.8 (high risk) for blood. A direct correlation was established between impaired vaccine-induced immunity to measles and elevated Mn and benzene levels (R2 = 0.19–0.26; b0 = (-1.19) – (-3.10); b1 = 32.50–39.59; р < 0.001); diphtheria and elevated Mn, Cr and Ni levels (R2 = 0.13–0.78; b0 = (-2.95) – (-4.19) b1 = 85.22–302.60; р < 0.001)); pertussis and elevated Mn level (R2 = 0.19; b0 = -1.19; b1 = 39.59; р < 0.001). Mn (0.0210 ± 0.0012 µg/cm3) and benzene (0.00072 ± 0.00020 µg/cm3) levels resulted in 1.7 times lower levels of JgG to measles and thrice as high likelihood of low seroprotection (OR = 3.0; CI = 1.68–5.31). Elevated levels of Mn, Ni (0.0057 ± 0.0007 µg/cm 3) and Cr (0.0061 ± 0.0008 µg/cm 3)were associated with 1.8 times lower levels of antibodies to diphtheria and 4 times higher likelihood of low seroprotection in primary schoolchildren (OR = 3.92; CI = 1.10–13.97). Mn occurrence in blood reduced levels of antibodies to pertussis by 1.4 times and increased likelihood of impaired specific immunity by 1.8 times (OR = 1.77; CI = 1.25–2.51). Creation of high-level vaccine-induced immunity to preventable infections in children with metals and aromatic hydrocarbons in blood requires serologic monitoring, additions made in the National calendar for preventive vaccination and implementation of specialized medical and preventive technologies.