HERD IMMUNITY AND RING VACCINATION

Öz

Immunization services are one of the most important public health interventions to protect people from diseases and prevent deaths. Although vaccines have been developed against more than 20 diseases today, many people have insufficient access to vaccines. However, it is preferable to vaccinate not only some people but also the entire society. In this context, herd immunity is mentioned. Herd immunity reduces the risk of encounters that will cause disease transmission to other people, thanks to those who have become immune to that disease as a result of vaccination or exposure to the disease. In this way, it is ensured that epidemics are prevented and morbidity and mortality are limited in a possible epidemic. In order to talk about herd immunity, society should be immune to a certain extent, with varying values for each disease. This; is sometimes economic, logistics etc. when this is not possible due to various factors, other immunization strategies such as ring vaccination may be considered. Ring vaccination aims to create an immune buffer around the case by vaccinating everyone in a "ring" around the infected case. It can be used as a complement to herd immunity or be preferred as the only immunization strategy in societies with insufficient resources if herd immunity cannot be provided and in sporadic diseases. This approach is under evaluation in terms of its applicability in certain situations in the COVID-19 outbreak.

Anahtar Kelimeler

• Vaccine
• Herd İmmunity
• Ring Vaccination
• COVID-19

TOPLUM BAĞIŞIKLIĞI VE HALKA BAĞIŞIKLAMA

Öz

Bağışıklama hizmetleri, insanların hastalıklardan korunmasında ve ölümlerin önüne geçmede son derece önemli halk sağlığı müdahalelerinden biridir. Günümüzde 20’den fazla hastalığa karşı aşı geliştirilmiş olmakla birlikte pek çok kişinin aşılara erişimi yetersizdir. Bununla birlikte sadece bazı kişilerin değil, toplumun tamamının aşılanması tercih edilmektedir. Bu kapsamda toplum bağışıklığından bahsedilmektedir. Toplum bağışıklığı, aşı veya hastalığı geçirme sonucu o hastalığa karşı bağışıklık kazananlar sayesinde diğer kişiler için hastalık bulaşmasına neden olacak karşılaşma riskini azaltır. Bu sayede salgınların önlenmesi ve olası bir salgında da morbidite ve mortalitenin sınırlanması sağlanır. Toplum bağışıklığından bahsedebilmek için her hastalık için değişen değerlerde, toplumun belli bir oranda bağışık olması gerekmektedir. Bu; bazen ekonomik, lojistik vb. etkenler sebebiyle mümkün olamadığında halka bağışıklama (ring vaccination) gibi başka bağışıklama stratejilerinin düşünülmesi söz konusu olabilmektedir. Halka bağışıklığı, enfekte vaka etrafındaki bir "halka" içindeki herkesin aşılanması ile vaka etrafında bir bağışıklık tamponu oluşturmayı amaçlamaktadır. Toplum bağışıklığını tamamlayıcı olarak kullanılabileceği gibi yetersiz kaynak olan toplumlarda toplum bağışıklığı sağlanamıyorsa ve sporadik olarak görülen hastalıklarda tek bağışıklama stratejisi olarak da tercih edilebilmektedir. Bu yaklaşım, COVID-19 salgınında belli durumlarda da uygulanabilirliği açısından değerlendirme aşamasındadır.

Anahtar Kelimeler

• Aşı
• Toplum Bağışıklığı
• Halka Bağışıklama
• COVID-19

Teşekkür

Yazının Hazırlanmasında Emeği Geçen: Prof. Dr. Meltem ÇÖL Ankara Üniversitesi Halk Sağlığı Anabilim Dalı

Kaynakça

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