Neutralization of Rubella Vaccine Virus and Immunodeficiency-Related Vaccine-Derived Rubella Viruses by Intravenous Immunoglobulins.

The association between granulomas and vaccine-derived rubella virus (VDRV) in people with primary immunodeficiencies has raised concerns about the ability of immunoglobulin preparations to neutralize VDRVs. We investigated the capacity of immunoglobulin to neutralize rubella vaccine virus and 4 VDRV strains. As expected, the rubella vaccine virus itself was potently neutralized by immunoglobulin preparations, but the VDRV isolates from patients after intrahost evolution, 2-6 times less so. Diagnosis of immune deficiencies before possible live-virus vaccination is thus of critical importance, while immunoglobulin replacement therapy can be expected to provide protection from rubella virus infection.

The occurrence of granulomas associated with vaccine-derived rubella viruses (VDRVs) in people with primary immunodeficiencies challenges immunoglobulin preparations regarding their rubella neutralizing ability. This study confirmed potent rubella virus neutralization capacity of immunoglobulin preparations and thus suggests protection against rubella in immunoglobulin-treated patients with primary immunodeficiency. It also highlights the importance of early diagnosis and timely given immunoglobulin to prevent possible systemic spread of VDRV persisting locally in granulomas.

Public Health Actions to Control Measles Among Afghan Evacuees During Operation Allies Welcome - United States, September-November 2021.

On August 29, 2021, the United States government oversaw the emergent establishment of Operation Allies Welcome (OAW), led by the U.S. Department of Homeland Security (DHS) and implemented by the U.S. Department of Defense (DoD) and U.S. Department of State (DoS), to safely resettle U.S. citizens and Afghan nationals from Afghanistan to the United States. Evacuees were temporarily housed at several overseas locations in Europe and Asia* before being transported via military and charter flights through two U.S. international airports, and onward to eight U.S. military bases,† with hotel A used for isolation and quarantine of persons with or exposed to certain infectious diseases.§ On August 30, CDC issued an Epi-X notice encouraging public health officials to maintain vigilance for measles among Afghan evacuees because of an ongoing measles outbreak in Afghanistan (25,988 clinical cases reported nationwide during January-November 2021) (1) and low routine measles vaccination coverage (66% and 43% for the first and second doses, respectively, in 2020) (2).

Infectious vaccine-derived rubella viruses emerge, persist, and evolve in cutaneous granulomas of children with primary immunodeficiencies.

Rubella viruses (RV) have been found in an association with granulomas in children with primary immune deficiencies (PID). Here, we report the recovery and characterization of infectious immunodeficiency-related vaccine-derived rubella viruses (iVDRV) from diagnostic skin biopsies of four patients. Sequence evolution within PID hosts was studied by comparison of the complete genomic sequences of the iVDRVs with the genome of the vaccine virus RA27/3. The degree of divergence of each iVDRV correlated with the duration of persistence indicating continuous intrahost evolution. The evolution rates for synonymous and nonsynonymous substitutions were estimated to be 5.7 x 10-3 subs/site/year and 8.9 x 10-4 subs/site/year, respectively. Mutational spectra and signatures indicated a major role for APOBEC cytidine deaminases and a secondary role for ADAR adenosine deaminases in generating diversity of iVDRVs. The distributions of mutations across the genes and 3D hotspots for amino acid substitutions in the E1 glycoprotein identified regions that may be under positive selective pressure. Quasispecies diversity was higher in granulomas than in recovered infectious iVDRVs. Growth properties of iVDRVs were assessed in WI-38 fibroblast cultures. None of the iVDRV isolates showed complete reversion to wild type phenotype but the replicative and persistence characteristics of iVDRVs were different from those of the RA27/3 vaccine strain, making predictions of iVDRV transmissibility and teratogenicity difficult. However, detection of iVDRV RNA in nasopharyngeal specimen and poor neutralization of some iVDRV strains by sera from vaccinated persons suggests possible public health risks associated with iVDRV carriers. Detection of IgM antibody to RV in sera of two out of three patients may be a marker of virus persistence, potentially useful for identifying patients with iVDRV before development of lesions. Studies of the evolutionary dynamics of iVDRV during persistence will contribute to development of infection control strategies and antiviral therapies.

Descriptive epidemiology of rubella disease and associated virus strains in Uganda.

Rubella virus causes a mild disease; however, infection during the first trimester of pregnancy may lead to congenital rubella syndrome (CRS) in over 80% of affected pregnancies. Vaccination is recommended and has been shown to effectively reduce CRS incidence. Uganda plans to introduce routine rubella vaccination in 2019. The World Health Organization recommends assessing the disease burden and obtaining the baseline molecular virological data before vaccine introduction. Sera collected during case-based measles surveillance from January 2005 to July 2018 were tested for rubella immunoglobulin M (IgM) antibodies. Sera from confirmed rubella outbreaks from January 2012 to August 2017 were screened using real-time reverse-transcription polymerase chain reaction (RT-PCR); for positive samples, a region within the E1 glycoprotein coding region was amplified and sequenced. Of the 23 196 suspected measles cases serologically tested in parallel for measles and rubella, 5334 (23%) were rubella IgM-positive of which 2710 (50.8%) cases were females with 2609 (96.3%) below 15 years of age. Rubella IgM-positive cases were distributed throughout the country and the highest number was detected in April, August, and November. Eighteen (18%) of the 100 sera screened were real-time RT-PCR-positive of which eight (44.4%) were successfully sequenced and genotypes 1G and 2B were identified. This study reports on the seroprevalence and molecular epidemiology of rubella. Increased knowledge of former and current rubella viruses circulating in Uganda will enhance efforts to monitor the impact of vaccination as Uganda moves toward control and elimination of rubella and CRS.

Outcomes for Nitazoxanide Treatment in a Case Series of Patients with Primary Immunodeficiencies and Rubella Virus-Associated Granuloma.

PURPOSE: Nitazoxanide was recently reported as having in vitro effectiveness against the rubella virus. Immunodeficiency-related vaccine-derived rubella occurs in some patients who have an inherited immunodeficiency and who received the MMR vaccine. This study investigated the in vivo effectiveness of nitazoxanide therapy. METHODS: This is a retrospective analysis of seven patients treated with nitazoxanide as salvage therapy for immunodeficiency-related vaccine-derived rubella infection. The patients were recruited from an ongoing rubella detection surveillance project. RESULTS: Seven patients with persistent rubella were treated with nitazoxanide and one demonstrated significant clinical improvement. Two additional patients exhibited diminished viral capsid production with one patient having transient slowing of progression. The cohort overall generally had low T cell counts and had a high burden of comorbidities. There were three deaths. Two deaths were from PML and one was related to hematopoietic stem cell transplantation. CONCLUSIONS: Nitazoxanide has limited in vivo anti-viral effects for immunodeficiency-related vaccine-derived rubella. Most patients did not exhibit clinical improvement.

Use of FTA Cards To Transport Throat Swabs and Oral Fluid Samples for Molecular Detection and Genotyping of Measles and Rubella Viruses.

The genetic characterization of measles viruses is an important tool for measles surveillance. Reverse cold chain requirements for the transportation of samples to reference laboratories are challenging in resource-limited settings. FTA cards facilitate the transport of virologic samples at ambient temperature as noninfectious material; however, the utility of FTA cards for the detection and genotyping of measles virus from clinical samples has not been evaluated. Throat swabs (TS) and oral fluid (OF) samples were collected from suspected measles cases in the Democratic Republic of the Congo. Virus detection (reverse transcription-quantitative real-time PCR [RT-qPCR]) and genotyping (endpoint RT-PCR) were compared for samples from 238 suspected cases; these samples were either transported using the reverse cold chain or at ambient temperature on FTA cards. Virus detection showed excellent positive agreement for OF samples compared to TS (95.3%; confidence interval [CI], 91.6 to 97.4), in contrast to 79.4% (CI, 73.5 to 84.3) for TS on FTA, and 85.5% (CI, 80.2 to 89.6) for OF on FTA compared to OF samples. Genotyping results obtained for a subset of samples indicated that 77.3% of all TS and 71.0% of OF samples would produce genotype information compared to 41.6% of TS and 41.3% of OF on FTA cards. Similar results were found for 16 measles-negative samples that were confirmed as rubella cases. Measles genotype B3 and rubella genotype 2B were detected. FTA cards have limited utility for virologic surveillance of sporadic cases of measles; however, they can be a useful tool for the expansion of virologic surveillance in countries where the reverse cold chain is not available.

Prevalence of Granulomas in Patients With Primary Immunodeficiency Disorders, United States: Data From National Health Care Claims and the US Immunodeficiency Network Registry.

PURPOSE: Granulomas are a potentially severe condition that can last for several years in persons with primary immunodeficiency disorders (PIDD). We assessed the prevalence of granulomas in patients with PIDD. METHODS: We used the Truven Health MarketScan® 2005-2015 Commercial Claims and Encounters and 2006-2015 Medicaid databases and the US Immunodeficiency Network (USIDNET) PIDD registry (a program of the Immune Deficiency Foundation). Our study population consisted of persons age < 65 years with PIDD, defined as persons with ≥ 2 claims with a diagnostic code for PIDD in MarketScan databases, or patients enrolled in USIDNET. Granulomas were identified using diagnostic codes in MarketScan or provider report in USIDNET. We calculated annual prevalence of PIDD and of granulomas among PIDD patients. RESULTS: We identified 247,474 and 40,395 persons with PIDD among commercially and Medicaid-insured persons, respectively. PIDD prevalence was 6.0/10,000 in 2005 and 11.7/10,000 in 2015 among commercially insured persons and 5.5/10,000 in 2006 and 9.6/10,000 in 2015 among Medicaid-insured persons. The prevalence of granulomas among PIDD patients was 1.2 and 1.5% among commercially and Medicaid-insured persons, respectively. In USIDNET, prevalence of granulomas was 4.4% (177/4021). The proportion with granulomas was similar across age groups in MarketScan, but varied from 2 to 9% in USIDNET. The reported prevalence of granulomas differed depending on PIDD condition: 1-2% in the MarketScan data and 0-13% in USIDNET. CONCLUSION: Granuloma prevalence in PIDD patients was 1-4%. Our study provides an estimate of the proportion of PIDD patients and suggests that granulomas are an uncommon occurrence among patients with PIDD.

Epidemiology of rubella infection and genotyping of rubella virus in Cote d'Ivoire, 2012-2016.

Rubella is a contagious disease caused by the rubella virus (RuV) that can lead to serious birth defects when women are infected in early pregnancy. This study aimed to describe the epidemiology and genetic diversity of rubella viruses in Cote d'Ivoire (CIV). Blood or oral fluid samples collected from suspected measles cases were first tested for the presence of measles specific IgM antibodies by enzyme-linked immunosorbent assay (ELISA). All measles IgM negative or indeterminate samples were tested for rubella IgM antibody using ELISA. Rubella-IgM-positive samples were tested by real-time reverse transcription polymerase chain reaction (RT-PCR) for the presence of rubella virus RNA. Real-time RT-PCR-positive RNA samples were used as template to amplify the 739 nt region used for rubella genotyping. PCR-positive samples were sequenced and phylogenetic analysis performed. Between 2012 and 2016, 4121 serums and 126 oral fluids were collected through the measles surveillance system. Of these, 3823 and 108 respectively were measles IgM negative or indeterminate. Subsequent testing for rubella found that 690 of 3823 (18%) serum samples and 25 of 108 (23%) oral fluid samples were rubella IgM-positive. The 739 nt segment of the E1 glycoprotein gene was amplified and sequenced for two serums and seven oral fluids samples. Phylogenetic analysis showed that the rubella viruses from CIV belonged to genotypes 1G (eight samples) and 2B (one sample). Rubella virus genotype 2B was found in CIV for the first time. These data contribute to baseline information on rubella virus strains found in CIV before the introduction of rubella vaccine.

Expansion of Surveillance for Vaccine-preventable Diseases: Building on the Global Polio Laboratory Network and the Global Measles and Rubella Laboratory Network Platforms.

Laboratory networks were established to provide accurate and timely laboratory confirmation of infections, an essential component of disease surveillance systems. The World Health Organization (WHO) coordinates global laboratory surveillance of vaccine-preventable diseases (VPDs), including polio, measles and rubella, yellow fever, Japanese encephalitis, rotavirus, and invasive bacterial diseases. In addition to providing high-quality laboratory surveillance data to help guide disease control, elimination, and eradication programs, these global networks provide capacity-building and an infrastructure for public health laboratories. There are major challenges with sustaining and expanding the global laboratory surveillance capacity: limited resources and the need for expansion to meet programmatic goals. Here, we describe the WHO-coordinated laboratory networks supporting VPD surveillance and present a plan for the further development of these networks.

Assessment of National Public Health and Reference Laboratory, Accra, Ghana, within Framework of Global Health Security.

The Second Year of Life project of the Global Health Security Agenda aims to improve immunization systems and strengthen measles and rubella surveillance, including building laboratory capacity. A new laboratory assessment tool was developed by the Centers for Disease Control and Prevention to assess the national laboratory in Ghana to improve molecular surveillance for measles and rubella. Results for the tool showed that the laboratory is well organized, has a good capacity for handling specimens, has a good biosafety system, and is proficient for diagnosis of measles and rubella by serologic analysis. However, there was little knowledge about molecular biology and virology activities (i.e., virus isolation on tissue culture was not available). Recommendations included training of technical personnel for molecular techniques and advocacy for funding for laboratory equipment, reagents, and supplies.

Noninterference of Rotavirus Vaccine With Measles-Rubella Vaccine at 9 Months of Age and Improvements in Antirotavirus Immunity: A Randomized Trial.

BACKGROUND: The burden of rotavirus morbidity and mortality is high in children aged <5 years in developing countries, and evaluations indicate waning protection from rotavirus immunization in the second year. An additional dose of rotavirus vaccine may enhance the immune response and lengthen the period of protection against disease, but coadministration of this dose should not interfere with immune responses to concurrently given vaccines. METHODS: A total of 480 9-month-old participants from Matlab, Bangladesh, were enrolled in a study with a primary objective to establish noninferiority of concomitant administration of measles-rubella vaccine (MR) and a third dose of human rotavirus vaccine (HRV; MR + HRV), compared with MR given alone. Secondary objectives included noninferiority of rubella antibody seroconversion and evaluating rotavirus IgA/IgG seroresponses in MR + HRV recipients. RESULTS: Two months after vaccination, 75.3% and 74.3% of MR + HRV and MR recipients, respectively, had seroprotective levels of measles virus antibodies; 100.0% and 99.6%, respectively, showed anti-rubella virus immunoglobulin G (IgG) seroprotection. In the MR + HRV group, antirotavirus immunoglobulin A and IgG seropositivity frequencies before vaccination (52.7% and 66.3%, respectively) increased to 69.6% and 88.3% after vaccination. CONCLUSIONS: Vaccine-induced measles and rubella antibody responses are not negatively affected by concomitant administration of HRV. The HRV dose increases antirotavirus serum antibody titers and the proportion of infants with detectable antirotavirus antibody. CLINICAL TRIALS REGISTRATION: NCT01700621.

Rubella.

Rubella remains an important pathogen worldwide, with roughly 100,000 cases of congenital rubella syndrome estimated to occur every year. Rubella-containing vaccine is highly effective and safe and, as a result, endemic rubella transmission has been interrupted in the Americas since 2009. Incomplete rubella vaccination programmes result in continued disease transmission, as evidenced by recent large outbreaks in Japan and elsewhere. In this Seminar, we provide present results regarding rubella control, elimination, and eradication policies, and a brief review of new laboratory diagnostics. Additionally, we provide novel information about rubella-containing vaccine immunogenetics and review the emerging evidence of interindividual variability in humoral and cell-mediated innate and adaptive immune responses to rubella-containing vaccine and their association with haplotypes and single-nucleotide polymorphisms across the human genome.

Assessing Immunity to Rubella Virus: a Plea for Standardization of IgG (Immuno)assays.

Immunity to rubella virus (RV) is commonly determined by measuring specific immunoglobulin G (RV IgG). However, RV IgG results and their interpretation may vary, depending on the immunoassay, even though most commercial immunoassays (CIAs) have been calibrated against an international standard and results are reported in international units per milliliter. A panel of 322 sera collected from pregnant women that tested negative or equivocal for RV IgG in a prior test (routine screening) was selected. This panel was tested with two reference tests, immunoblotting (IB) and neutralization (Nt), and with 8 CIAs widely used in Europe. IB and Nt gave concordant results on 267/322 (82.9%) sera. Of these, 85 (26.4%) sera were negative and 182 (56.5%) sera were positive for both tests. All 85 IB/Nt-negative samples were classified as negative with all CIAs. Of the 182 IB/Nt-positive samples, 25.3 to 61.5% were classified as equivocal and 6 to 64.8% were classified as positive with the CIAs. Wide variations in titers in international units per milliliter were observed. In our series, more than half of the women considered susceptible to RV based on CIA results tested positive for RV antibodies by IB/Nt. Our data suggest that (i) sensitivity of CIAs could be increased by considering equivocal results as positive and (ii) the definition of immunity to RV as the 10-IU/ml usual cutoff as well as the use of quantitative results for clinical decisions may warrant reconsideration. A better standardization of CIAs for RV IgG determination is needed.

Genotypes of rubella virus and the epidemiology of rubella infections in the Democratic Republic of the Congo, 2004-2013.

Rubella is a viral infection that may cause fetal death or congenital defects, known as congenital rubella syndrome (CRS), during early pregnancy. The World Health Organization (WHO) recommends that countries assess the burden of rubella and CRS, including the determination of genotypes of circulating viruses. The goal of this study was to identify the genotypes of rubella viruses in the Democratic Republic of the Congo (DRC). Serum or throat swab samples were collected through the measles surveillance system. Sera that tested negative for measles IgM antibody were tested for rubella IgM antibody. Serum collected within 4 days of rash onset and throat swabs were screened by real-time RT-PCR for rubella virus RNA. For positive samples, an amplicon of the E1 glycoprotein gene was amplified by RT-PCR and sequenced. 11733 sera were tested for rubella IgM and 2816 (24%) were positive; 145 (5%) were tested for the presence of rubella RNA by real-time RT-PCR and 10 (7%) were positive. Seventeen throat swabs were analyzed by RT-PCR and three were positive. Sequences were obtained from eight of the positive samples. Phylogenetic analysis showed that the DRC rubella viruses belonged to genotypes 1B, 1E, 1G, and 2B. This report provides the first information on the genotypes of rubella virus circulating in the DRC. These data contribute to a better understanding of rubella burden and the dynamics of rubella virus circulation in Africa. Efforts to establish rubella surveillance in the DRC are needed to support rubella elimination in Africa. J. Med. Virol. 88:1677-1684, 2016. © 2016 Wiley Periodicals, Inc.

Global Measles and Rubella Laboratory Network Support for Elimination Goals, 2010-2015.

In 2012, the World Health Assembly endorsed the Global Vaccine Action Plan (GVAP)* with the objective to eliminate measles and rubella in five World Health Organization (WHO) regions by 2020. In September 2013, countries in all six WHO regions had established measles elimination goals, and additional goals for elimination of rubella and congenital rubella syndrome were established in three regions (1). Capacity for surveillance, including laboratory confirmation, is fundamental to monitoring and verifying elimination. The 2012-2020 Global Measles and Rubella Strategic Plan of the Measles and Rubella Initiative(†) calls for effective case-based surveillance with laboratory testing for case confirmation (2). In 2000, the WHO Global Measles and Rubella Laboratory Network (GMRLN) was established to provide high quality laboratory support for surveillance (3). The GMRLN is the largest globally coordinated laboratory network, with 703 laboratories supporting surveillance in 191 countries. During 2010-2015, 742,187 serum specimens were tested, and 27,832 viral sequences were reported globally. Expansion of the capacity of the GMRLN will support measles and rubella elimination efforts as well as surveillance for other vaccine-preventable diseases (VPDs), including rotavirus, and for emerging pathogens of public health concern.

Epidemiological and molecular investigation of a rubella outbreak, Romania, 2011 to 2012.

We describe a rubella outbreak that occurred in Romania between September 2011 and December 2012. During this period 24,627 rubella cases, 41.1% (n=10,134) of which female, were notified based on clinical criteria, and a total of 6,182 individuals were found serologically positive for IgM-specific rubella antibody. The median age of notified cases was 18 years (range: <1-65) and the most affected age group 15 to 19 years (n=16,245 cases). Of all notified cases, 24,067 cases (97.7%) reported no history of vaccination. Phylogenetic analysis of 19 sequences (739 nucleotides each), from 10 districts of the country revealed that the outbreak was caused by two distinct rubella virus strains of genotype 2B, which co-circulated with both temporal and geographical overlap. In addition to the 6,182 IgM-positive rubella cases, 28 cases of congenital rubella syndrome (CRS) were identified, including 11 neonatal deaths and one stillbirth. The outbreak underscores the need to encourage higher vaccination uptake in the population, particularly in women of reproductive age, and to strengthen epidemiological and laboratory investigations of suspected rubella cases. Genetic characterisation of wild-type rubella virus is an essential component to enhance surveillance and here we report rubella virus sequences from Romania.

Identification of Serologic Markers for School-Aged Children With Congenital Rubella Syndrome.

BACKGROUND: Congenital rubella syndrome (CRS) case identification is challenging in older children since laboratory markers of congenital rubella virus (RUBV) infection do not persist beyond age 12 months. METHODS: We enrolled children with CRS born between 1998 and 2003 and compared their immune responses to RUBV with those of their mothers and a group of similarly aged children without CRS. Demographic data and sera were collected. Sera were tested for anti-RUBV immunoglobulin G (IgG), IgG avidity, and IgG response to the 3 viral structural proteins (E1, E2, and C), reflected by immunoblot fluorescent signals. RESULTS: We enrolled 32 children with CRS, 31 mothers, and 62 children without CRS. The immunoblot signal strength to C and the ratio of the C signal to the RUBV-specific IgG concentration were higher (P < .029 for both) and the ratio of the E1 signal to the RUBV-specific IgG concentration lower (P = .001) in children with CRS, compared with their mothers. Compared with children without CRS, children with CRS had more RUBV-specific IgG (P < .001), a stronger C signal (P < .001), and a stronger E2 signal (P ≤ .001). Two classification rules for children with versus children without CRS gave 100% specificity with >65% sensitivity. CONCLUSIONS: This study was the first to establish classification rules for identifying CRS in school-aged children, using laboratory biomarkers. These biomarkers should allow improved burden of disease estimates and monitoring of CRS control programs.

Congenital rubella syndrome in child of woman without known risk factors, New Jersey, USA.

We report a case of congenital rubella syndrome in a child born to a vaccinated New Jersey woman who had not traveled internationally. Although rubella and congenital rubella syndrome have been eliminated from the United States, clinicians should remain vigilant and immediately notify public health authorities when either is suspected.

Genomic analysis of the Chinese genotype 1F rubella virus that disappeared after 2002 in China.

Genotype 1F was likely localized geographically to China as it has not been reported elsewhere. In this study, whole genome sequences of two rubella 1F virus isolates were completed. Both viruses contained 9,761 nt with a single nucleotide deletion in the intergenic region, compared to the NCBI rubella reference sequence (NC 001545). No evidence of recombination was found between 1F and other rubella viruses. The genetic distance between 1F viruses and 10 other rubella virus genotypes (1a, 1B, 1C, 1D, 1E, 1G, 1J 2A, 2B, and 2C) ranged from 3.9% to 8.6% by pairwise comparison. A region known to be hypervariable in other rubella genotypes was also the most variable region in the 1F genomes. Comparisons to all available rubella virus sequences from GenBank identified 22 nucleotide variations exclusively in 1F viruses. Among these unique variations, C9306U is located within the recommended molecular window for rubella virus genotyping assignment, could be useful to confirm 1F viruses. Using the Bayesian Markov Chain Monte Carlo (MCMC) method, the time of the most recent common ancestor for the genotype 1F was estimated between 1976 and 1995. Recent rubella molecular surveillance suggests that this indigenous strain may have circulated for less than three decades, as it has not been detected since 2002.

Phylogenetic analysis of rubella viruses identified in Uganda, 2003-2012.

Molecular data on rubella viruses are limited in Uganda despite the importance of congenital rubella syndrome (CRS). Routine rubella vaccination, while not administered currently in Uganda, is expected to begin by 2015. The World Health Organization recommends that countries without rubella vaccination programs assess the burden of rubella and CRS before starting a routine vaccination program. Uganda is already involved in integrated case-based surveillance, including laboratory testing to confirm measles and rubella, but molecular epidemiologic aspects of rubella circulation have so far not been documented in Uganda. Twenty throat swab or oral fluid samples collected from 12 districts during routine rash and fever surveillance between 2003 and 2012 were identified as rubella virus RNA positive and PCR products encompassing the region used for genotyping were sequenced. Phylogenetic analysis of the 20 sequences identified 19 genotype 1G viruses and 1 genotype 1E virus. Genotype-specific trees showed that the Uganda viruses belonged to specific clusters for both genotypes 1G and 1E and grouped with similar sequences from neighboring countries. Genotype 1G was predominant in Uganda. More epidemiological and molecular epidemiological data are required to determine if genotype 1E is also endemic in Uganda. The information obtained in this study will assist the immunization program in monitoring changes in circulating genotypes.