ObjectivesTo systematically review the clinical characteristics of pregnant females and juveniles (<18 years) with Middle East Respiratory Syndrome (MERS), so as to provide evidence for epidemic prevention and treatment of COVID-19.MethodsPubMed, EMbase, Web of Science, The Cochrane Library, CNKI, VIP and WanFang Data databases were electronically searched to collect studies on clinical characteristics of pregnant females and juveniles with MERS from inception to February 15th, 2020. Two reviewers independently screened literature, extracted data and assessed risk of bias of included studies. Descriptive analysis was then performed.ResultsA total of 12 studies involving 12 pregnant females, and 21 juveniles with MERS were included. The results of studies showed that the male to female ratio of juveniles patients was 1 to 1.63 and the age ranged from 9 months to 16 years. The primary transmission route of juveniles cases was family contact infection, accounting for 57.1% (12/21). Asymptomatic juveniles accounted for 57.1% (12/21), and the most common symptoms were fever, cough and shortness of breath. Some patients exhibited gastrointestinal symptoms such as vomiting and diarrhea. The positive rate of MERS-CoV RCT test was 100.0% (21/21). As for chest radiograph, 73.7% (14/19) cases showed no obvious lesions, and juveniles with lesions were mainly bilateral. 3 patients with underlying diseases developed severe cases, the mortality was 9.5% (2/21). The age range of pregnant women was 27 to 39, with the gestational age from 6 to 38 weeks. The primary transmission route for pregnant women was nosocomial infection, accounting for 57.1% (4/7). Fever, cough, shortness of breath were common manifestations, while abdominal pain occurred in two female patients. The positive rate of MERS-CoV RCT test was 100.0% (11/11). The chest radiograph findings were mainly bilateral lesions, accounting for 55.6% (5/9). 80.0% of whole pregnant females were severe cases (8/10), 4 of them died, with the 50.0% (4/8) mortality in severe pregnant cases. Among the infective pregnant women, 2 were stillborn and 10 were delivered, of which 1 died due to premature delivery. The remaining 9 surviving newborns were not infected with MERS-CoV and there was no evidence of mother-to-child transmission.ConclusionsThe clinical symptoms of MERS in juveniles are similar to those in adults, however, considerably milder. Severe case rate is higher in patients with underlying diseases. However, maternal infections could be much severe with higher mortality. It is particularly important to strengthen the management of pregnant females, especially prevent hospital infection. There is still no evidence of MERS-CoV mother-to-child transmission.