Figure 1: Number of cases measles (n=45) and rubella (n=0), by week of rash onset, as reported to the Canadian Measles/ Rubella Surveillance System (CMRSS) and Measles and Rubella Surveillance system (MARS), for the period ending February 21, 2015.
During epidemiological week 07, 2015, 18 measles cases were reported, by Ontario (n=6) and Quebec (n=12). Rash onset for these cases occurred during week 06 (n= 5) and week 07 (n= 13).
The year-to-date total is 45 cases of measles and 0 cases of rubella for 2015.
Note that when additional cases are reported in advance of the cycle, these cases will be described in the appropriate reporting cycle.
Figure 2: Distribution of confirmed measles and rubella cases by health region. Cases are included if they are considered activeFigure 2 - Footnote *.
To date in 2015, 23 measles cases have been genotyped and the genotypes were: D4 (n=16), B3 (n=6) and D8 (n=1).
Of the 19 reported measles cases in Ontario, 16 cases have been genotyped. All have an identical genotype D4 strain, based on the standard N-450 sequence.
From Quebec, 6 cases were genotyped and were genotype B3, identical to the MVi/Harare.ZWE/38.09 sequence variant (GenBank accession number JF973033), and identical to the virus reported in a multi-state outbreak in the United States.
Finally, 1 case from Manitoba, with travel history to India, was genotype D8 which is endemic in IndiaFootnote 2.
Figure 3: Distribution of measles genotypes detected in 2015 (n=23) by week of rash onset (if available, n=21) or specimen collection (n=2). Epidemiological weeks are assigned in accordance with WHO guidelines (WHO.WER.2012;9(87):73) with week 1 beginning on the first Monday of the year.
The current global distribution of measles genotypes can be found on the WHO Measles Nucleotide Surveillance (MeaNS) website.
For information regarding the interpretation and use of measles genotyping (including a discussion of genotypes and sequence variants), refer to Hiebert J and Severini A. Canada Communicable Disease Report. 2014; 40-12: 257- 260.