Department of Pediatrics, Bharati Vidyapeeth (Deemed To Be University) Medical College, Pune, India.
Interactive Research School for Health Affairs (IRSHA), Bharati Vidyapeeth (Deemed To Be University), Pune, India.
Vaccine. 2019 Mar 7;37(11):1443-1448. doi: 10.1016/j.vaccine.2019.01.043. Epub 2019 Feb 11.
Immunization of children with vaccines against Measles, Mumps, Rubella, and Varicella (MMRV) is practiced globally with varied recommendations. In India, measles vaccine is administered alone or as MMR at 9 months age. Varicella vaccine is not routinely used. Immunization age is a function of disappearance of maternal antibodies and natural exposure of the children to the pathogens. In view of the measles-WHO-initiative, we aimed to assess if the current immunization age for measles is still valid. In addition, the kinetics of IgG and IgM antibodies against rubella, mumps and varicella viruses was also examined.
This cross-sectional study was conducted at a tertiary care hospital in Pune, India. A total of 600 children, 150 each in 6-month/9-month (no vaccination) and 12-month/15-month (minimum 4 weeks post-measles-vaccine) cohorts were included. History of these infections and birth status (term/preterm) was recorded. All serum samples were screened for IgG-anti-MMRV-antibodies while IgG-positives were tested for specific IgM antibodies (ELISA).
At 6-months, the prevalence of MMRV antibodies was 4.7%, 2.7%, 10.7%, 5.3% respectively depicting disappearance of maternal antibodies in majority of the children. Birth status did not influence antibody positivity. Despite vaccination at ∼9-months, >25% children were still susceptible to measles virus at the age of 12/15-months. The ratio of clinical:subclinical infections was 4:10 (measles) and 12:1 (varicella). All the mumps/rubella IgM positives (1 and 2 respectively) represented subclinical infections.
Demonstration of early disappearance of maternal antibodies against MMRV viruses leading to the risk of these infections at an early age emphasize need for early immunization of Indian children. Suboptimal response to measles vaccine needs to be seriously addressed especially in view of the WHO's initiative for measles eradication.
全球范围内普遍对儿童进行麻疹、腮腺炎、风疹和水痘（MMRV）疫苗免疫接种，但推荐方案存在差异。在印度，麻疹疫苗单独使用或在 9 个月龄时与 MMR 联合使用。水痘疫苗未常规使用。免疫接种年龄取决于儿童体内母体抗体的消失和自然感染病原体的情况。鉴于世界卫生组织（WHO）发起的麻疹消除倡议，我们旨在评估目前的麻疹免疫接种年龄是否仍然有效。此外，我们还研究了风疹、腮腺炎和水痘病毒的 IgG 和 IgM 抗体的动力学。
这是在印度浦那的一家三级保健医院进行的横断面研究。共纳入 600 名儿童，每个年龄组 150 名，分别为 6 个月/9 个月（无疫苗接种）和 12 个月/15 个月（麻疹疫苗接种后至少 4 周）组。记录了这些感染的病史和出生情况（足月/早产）。所有血清样本均进行 MMRV 抗体 IgG 筛查，IgG 阳性者进行特异性 IgM 抗体（ELISA）检测。
6 个月时，MMRV 抗体的流行率分别为 4.7%、2.7%、10.7%和 5.3%，这表明大多数儿童体内的母体抗体已经消失。出生情况对抗体阳性率没有影响。尽管在约 9 个月龄时进行了疫苗接种，但仍有＞25%的儿童在 12/15 月龄时对麻疹病毒易感。麻疹（临床：亚临床感染比为 4：10）和水痘（临床：亚临床感染比为 12：1）的感染比例。所有腮腺炎/风疹 IgM 阳性者（分别为 1 和 2）均代表亚临床感染。
证明 MMRV 病毒的母体抗体早期消失导致这些感染在儿童早期发生的风险，强调印度儿童需要早期免疫接种。麻疹疫苗的反应不理想，特别是在 WHO 发起麻疹消除倡议的情况下，需要认真解决。
