Rubella is a disease of public health significance owing to its adverse effects during pregnancy and on pregnancy outcomes. Women who contract rubella virus during pregnancy may experience complications such as foetal death or give birth to babies born with congenital rubella syndrome. Vaccination against rubella is the most effective and economical approach to control the disease, and to avoid the long term effects and high costs of care for children with congenital rubella syndrome as well as to prevent death from complications. Zimbabwe commenced rubella surveillance in 1999, despite lacking a rubella vaccine in the national Expanded Programme on Immunization, as per the World Health Organization recommendation to establish a surveillance system to estimate the disease burden before introduction of a rubella vaccine. The purpose of this analysis is to describe the disease trends and population demographics of rubella cases that were identified through the Zimbabwe national measles and rubella case-based surveillance system during a 5-year period between 2007 and 2011. Data from the Zimbabwe National Measles Laboratory for the 5-year study period were analysed for age, sex, district of origin, seasonality, and rubella IgM serostatus. A total of 3428 serum samples from cases of suspected measles in all administrative districts of the country were received by the laboratory during this period. Cases included 51% males and 49% females. Of these, 2999 were tested for measles IgM of which 697 (23.2%) were positive. Of the 2302 measles IgM-negative samples, 865 (37.6%) were rubella IgM-positive. Ninety-eight percent of confirmed rubella cases were children younger than 15 years of age. Most infections occurred during the dry season. The national case-based surveillance revealed the disease burden and trends of rubella in Zimbabwe. These data add to the evidence for introducing rubella-containing vaccine into the national immunization programme.

With 762 laboratories, the Global Measles and Rubella Laboratory Network (GMRLN) is the largest laboratory network coordinated by the World Health Organization (WHO). Like the Global Polio Laboratory Network, the GMRLN has multiple tiers, including global specialized laboratories, regional reference laboratories, national laboratories, and, in some countries, subnational laboratories. Regional networks are supervised by regional laboratory coordinators reporting to a global coordinator at WHO headquarters. Laboratories in the GMRLN have strong links to national disease control and vaccination programs. The GMRLN’s goal is to support member states in obtaining timely, complete, and reliable laboratory-based surveillance data for measles and rubella as part of the strategy for achieving measles and rubella elimination. Surveillance data are reported to the national program and are included in annual reports on the status of measles and rubella elimination to national verification committees for review by regional verification commissions. Quality within the GMRLN is ensured by monitoring performance through external quality assurance programs, confirmatory and quality control testing, accreditation, and coordination of corrective action and training where needed. The overall performance of the laboratories has remained high over the years despite many challenges, particularly the COVID-19 pandemic. The GMRLN is well-positioned to support high-quality laboratory-based surveillance for measles and rubella and to transition to supporting laboratory testing for other pathogens, including vaccine-preventable diseases.

The Oral Polio Vaccine (OPV or Sabin) is genetically unstable and may mutate to form vaccine-derived polioviruses (VDPVs). In 2014, two VDPVs type 2 were identified during routine surveillance of acute flaccid paralysis (AFP) cases. Consequently, a retrospective VDPV survey was conducted to ensure that there was no circulating VDPV in the country. All Sabin poliovirus isolates identified in Uganda 6 months before and 6 months after were re-screened; Sabin 1 and 3 polioviruses were re-screened for Sabin 2 and Sabin 2 polioviruses were re-screened for VDPVs type 2. The Poliovirus rRT-PCR ITD/VDPV 4.0 assay and sequencing were used respectively. The first two VDPVs type2 were identified in Eastern Uganda and the third was identified during the survey from South-western Uganda. These regions had low OPV coverage and poor AFP surveillance indicators. The retrospective VDPV survey was a useful strategy to screen for VDPVs more exhaustively. Supplementary surveillance methods need to be encouraged.

There are 13 globally recognized rubella virus genotypes of which only 2 (1E and 2B) have been detected recently. The largest percentage of all reported rubella virus sequences come from China and Japan with Africa reporting limited data. In a bid to address the lack of rubella genotype data in Uganda and the World Health Organization Africa region, we sought to characterize rubella viruses retrospectively using sera collected from suspected measles patients that turned out rubella IgM positive. Seven sequences belonging to genotype 2B sub-lineage 2B-L2c were obtained. These sequences clustered with other genotype 2B sequences previously reported from Uganda. None of the other genotypes (1E and 1G) reported from Uganda in the earlier years were detected. In addition, none of the sequences were obtained after the introduction of the measles-rubella containing vaccine. The above highlight the need for continuous rubella virological surveillance to confirm interruption of endemic rubella genotype circulation.

Acute flaccid paralysis (AFP) is a rare side effect of the oral polio vaccine but can be associated with outbreaks and permanent disability in patients harboring circulating vaccine-derived polioviruses (cVDPVs). With the advancement of polio abolition in a glimpse, cVDPVs are causing outbreaks and slowing the polio eradication process. The polio virus protein 1 (VP1) contains the binding site that is key for virus transmission. Understanding the evolution of VP1 among AFP patients could yield more insight into the early events of cVDPVs. Polioviruses were identified from stool specimens of AFP patients using cell culture; and confirmed by the real time RT PCR intra-typic differentiation and vaccine-derived poliovirus assays. Seventy-nine (79) Sabin-like poliovirus 1 (SL1) and 86 Sabin-like poliovirus 3 (SL3) were sequenced. The VP1 amino acid substitutions T106A in Sabin poliovirus 1 and A54V in Sabin poliovirus 3 were common among the AFP patients as has been found in previous studies. Other substitutions that were associated with AFP were: T290A and A54T in SL1 and SL3 respectively. Nucleotide mutations that were common among the AFP patients included T402C, C670A, and T816C in SL1, and G22A, C375Y, A472R, and A694T in SL3 polioviruses. Characterizing mutations that are associated with AFP could contribute to efforts pursued to mitigate the risk of vaccine-derived polioviruses and promote development of safer vaccines.

The World Health Organization (WHO) Global Measles and Rubella Laboratory Network (GMRLN) collects molecular and epidemiological data to monitor progress towards the elimination of measles and rubella. This report summarises global trends from the data collected through the Measles virus Nucleotide Surveillance (MeaNS2) and Rubella virus Nucleotide Surveillance (RubeNS2) websites up to 2025, with a particular focus on measles virus (MeV). The analysis of MeaNS2 sequence submissions demonstrates substantial regional variations in the proportion of cases sequenced and predominant genotypes reported. Following a steep decrease in measles cases during the COVID-19 pandemic, numbers of reported cases and sequences have both rebounded. Only two of the 24 MeV genotypes originally recognised have been reported globally since 2021: B3 and D8. In response to the decrease in the genetic diversity of circulating strains, the number of sequences submitted for sub-genomic regions other than the N-450 used for genotyping has increased since 2022. The number of sequences submitted to RubeNS2 for rubella virus (RuV) is 10-fold lower than that reported for MeV, due to fewer detected cases and technical challenges of RuV sequencing. Only 59 RuV sequences of genotypes 1G and 2B have been reported since 2022. Continued investment in laboratory capacity, data quality, surveillance, epidemiological investigation, and vaccination programmes remain essential for sustaining the global measles and rubella elimination initiative.