Wednesday, 11 May 2016

Colombia Zika virus report, Epidemiological Week No. 17...

The latest epidemiological report, which includes data on Zika virus disease (ZVD; 24APR2016-30APR2016), has been produced by the Colombian National Institute for Health team.[1]
Graph No.1. The cumulative curve of confirmed ZVD cases 
(green circles, left-hand axis) and the change in confirmed ZVD case 
numbers when compared to the preceding week's total 
(green bars, right-hand axis). Data from [1]. 
Click on graph to enlarge.
Graph No. 1 shows that 1 fewer laboratory confirmed case of ZVD was reported this week than last. That's different. The total now at 3,751 or 5% of all the clinically suspected Zika virus (ZIKV) detections.

Graph No.2. The cumulative curve of suspectedZVD cases
(pink circles, left-hand axis) and the change in suspected ZVD case
numbers when compared to the preceding week's total
(red bars, right-hand axis). Data from [1].
Click on graph to enlarge.
Graph No. 2 shows the change in suspected cases. These are not laboratory confirmed. The suspected ZVD cases continue to rise in a linear fashion, adding 2,671 this week to total 68,634 suspected cases of ZVD.
Graph No.3. The cumulative curve of confirmed ZIKV infections 
(lilac circles, left-hand axis) and the change in confirmed ZIKV infection 
numbers when compared to the preceding week's total 
(purple bars, right-hand axis). Now added the reported umber of microcephaly cases 
confirmed as ZIKV infected (yellow bars, right-hand axis). To account for adjustments 
that take cases away when there is no weekly case growth, a negative 
value - the y-axes now allow for negative values. Data from [1]. 
Click on graph to enlarge.
Graph No. 3 shows that to Epidemiological Week No. 17, 11,724 suspected (+418) and 2,007 confirmed ZIKV infections (-1) have been identified in pregnant women. 

As of this report, 5 (an increase (+1) from last week) live births have been diagnosed with microcephaly/central nervous system disorders and were reported as being ZIKV positive; 32 (up from 26 last week) other microcephaly diagnoses are now under investigation.[1] That represents 0.25% of all confirmed ZIKV positive mothers.

It has now been 207 days, or about 7 months, since ZIKV was first confirmed in Colombia on 16th October 2015.[2] Colombia is currently carrying the next biggest load of Zika virus disease cases, after Brazil.[3]

Brazil first reported reported positive (but unconfirmed) laboratory tests for Zika virus disease on 29th April 2015. Brazil then started to report a rise in foetal anomalies (an initial 141), in the form of microcephaly on 30th October 2015. This was 184 days - or about 6 months later.[4]

References...

  1. http://www.ins.gov.co/boletin-epidemiologico/Boletn%20Epidemiolgico/2016%20Bolet%C3%ADn%20epidemiol%C3%B3gico%20semana%2017.pdf
  2. http://www.who.int/bulletin/online_first/16-171082/en/
  3. http://www.nature.com/news/first-zika-linked-birth-defects-detected-in-colombia-1.19502
  4. http://who.int/bulletin/online_first/16-171082/en/