Background: Despite the effective National Immunization Programme of Slovakia, some population groups are incompletely vaccinated or unvaccinated. We aimed to describe the measles outbreak spread in Eastern Slovakia between May and October 2018, affecting the Roma communities in relation to the existing immunity gaps.
Methods: We defined a group of persons living in socially closed communities with low vaccination coverage.
Results: Of 439 measles cases (median age: 10 years), 264 (60.1%) were vaccinated, 137 (31.2%) received two doses and 127 (28.9%) one dose of measles vaccines, 155 (35.3%) were unvaccinated and 20 (4.6%) had an unknown vaccination status. Samples from 102 patients (with two-dose vaccination status) were additionally tested for antibodies against rubella and mumps. Of 102 cases, 68 (66.7%) cases had a positive IgM and 23 (22.5 %) IgG antibodies against measles. For rubella, only 20 (19.6%) cases had seropositive IgG levels, for mumps higher positivity was detected in 60 persons (58.8%). We could detect only a small percentage with positive serology results of rubella IgG antibodies across all age groups. We have assumed that rubella antibodies had to be produced following the vaccination. Their absence in the cases with two doses of MMR suggests that these vaccines could not have been administrated despite the fact that this data was included in the medical records. Sequential analysis of two samples showed measles genotype B3.
Conclusion: This outbreak can outline the existence of a vulnerable group of the Roma. Low vaccinate coverage represents a serious public health threat.
Ozadje: Kljub učinkovitemu nacionalnemu programu imunizacije na Slovaškem so nekatere skupine prebivalcev nepopolno cepljene ali necepljene. Želeli smo opisati izbruh ošpic na vzhodnem Slovaškem med majem in oktobrom 2018, ki je prizadel romske skupnosti v povezavi z obstoječimi vrzelmi v imunosti.
Metode: Opredelili smo skupino ljudi, ki živijo v socialno zaprtih skupnostih z nizko precepljenostjo.
Rezultati: Med 439 primeri ošpic (mediana starost: 10 let) je bilo 264 ljudi cepljenih (60,1 %), 137 (31,2 %) jih je prejelo dva odmerka in 127 (28,9 %) en odmerek cepiva proti ošpicam, 155 (35,3 %) jih je bilo necepljenih, pri 20 (4,6 %) pa status cepljenja ni bil znan. Vzorce 102 bolnikov (s statusom cepljenja z dvema odmerkoma) smo dodatno testirali za protitelesa proti rdečkam in mumpsu. Od 102 primerov jih je 68 (66,7 %) imelo pozitiven rezultat za protitelesa IgM in 23 (22,5 %) za protitelesa IgG proti ošpicam. Kar zadeva rdečke, smo samo pri 20 (19,6 %) primerih ugotovili seropozitivne ravni IgG, medtem ko smo za mumps odkrili večjo pozitivnost pri 60 posameznikih (58,8 %). V vseh starostnih skupinah smo odkrili samo majhen odstotek posameznikov s pozitivnimi serološkimi rezultati za protitelesa IgG proti rdečkam. Predpostavili smo, da po cepljenju zagotovo nastanejo protitelesa proti rdečkam. Njihova odsotnost v primerih z dvema odmerkoma cepiva MMR nakazuje, da to cepivo ni moglo biti uporabljeno, čeprav so bili ti podatki vključeni v zdravstveno kartoteko. Sekvenčna analiza dveh vzorcev je pokazala genotip ošpic B3.
Sklep: Ta izbruh lahko kaže na obstoj ranljive skupine Romov. Nizka precepljenost pomeni resno grožnjo za javno zdravje.
Keywords: Roma, outbreak; measles; vaccination coverage.
© 2020 Henrieta Hudečková, Janka Stašková, Ján Mikas, Adriana Mečochová, Edita Staroňová, Alexandra Polčičová, Tibor Baška, Martin Novák, Nora Malinovská, Jana Zibolenová, Viera Švihrová, Elena Nováková, Mária Štefkovičová, published by Sciendo.