Zika Virus Surveillance and Reporting in the Caribbean

Preventing disease

Promoting and protecting health

Preventing disease, promoting and protecting health

Zika Virus (ZIKV)

Surveillance and Reporting

Dr. Joy St. John

Director

Surveillance, Disease-Prevention and Control Division

Caribbean Public Health Agency (CARPHA)


Outline

• Zika Virus (ZIKV)

– Global Movement of ZIKV

– ZIKV - Case Definition

– The Caribbean Situation

– ZIKV Testing Guidelines

– Feedback on Testing to date

– Surveillance for Neurological Sequelae

• Microcephaly

• Guillain Barre Syndrome

– The pregnancy question


GLOBAL MOVEMENT OF ZIKV

A History


194

7

Discovered in Uganda 1947


194

8

Expansion other countries in Africa 1947-1948


197

7

Pakistan, Malaysia, Indonesia 1977-1978


197

8

Pakistan, Malaysia, Indonesia 1977-1978


200

7

Yap Island (Micronesia) and Guam, 2007

200

7


201

3

Tahiti, French Polynesia, 2013


201

4

New Caledonia (FR) and Cook Islands, 2014 Easter Island (CHILE), 2014


201

5

Brazil, May 2015


201

6

Active transmission in the Americas 2016 (and other areas worldwide in previous 15 months, ECDC)


Case Definition

• The working case definition for Zika, is:

• Rash or elevated body temperature (> 37.2 °C) with one or more of the following symptoms, not

explained by other medical conditions

• Arthralgia or myalgia (joint or muscle pain)

• Non-purulent conjunctivitis or conjunctival hyperemia (reddened eyes, without mucous/discharge)

• Headache or malaise

AND

• History of travel to a region with reported transmission (see following slide)

– NB – travel history becomes less essential, the further ZIKV spreads through the

region


REGIONAL SITUATION


Regional Territories With Confirmed local ZIKV cases

CARPHA Member States • Aruba

• Barbados

• Bonaire

• Curaçao

• Guyana

• Haiti

• Jamaica

• Sint Maarten

• St. Vincent and the Grenadines

• Suriname

• Trinidad and Tobago

Non-CMS Caribbean Islands

• The

Dominican

Republic

• Guadeloupe

• Martinique

• Puerto Rico,

a US territory

• Saint Martin

(French)

• U.S. Virgin

Islands

Level 2 Travel Notices (Practice Enhanced Precautions) have been posted to the CDC Website for each

country *except USA


Regional Territories With Confirmed local ZIKV cases

• Bolivia

• Brazil

• Colombia

• Ecuador

• French Guiana

• Paraguay

• Venezuela

Level 2 Travel Notices (Practice Enhanced

Precautions) have been posted to the CDC

Website for each country *except USA

North American Territories

Central America

• Costa Rica

• El Salvador

• Guatemala

• Honduras

• Nicaragua

• Panama

South American

Territories

• Mexico

• USA

• *Sexual

transmission

(~15 cases)



ZIKV TESTING AT CARPHA


ZIKV Testing at CARPHA

• If suspected cases with compatible clinical and epidemiological features are found in

any CMS, CARPHA can provide diagnostic confirmation.

• ZIKV can only be confirmed by PCR in our Dengue-endemic region

– Extensive cross-reactivity between DENV IgM and ZIKV IgM makes serology

uninterpretable in our Member States

• Viraemia is highest within first 3 days of onset of symptoms and falls to undetectable

levels after day 5

• Samples should therefore be taken from suspect cases between day 1 (day of onset)

and day 5 and submitted to the local Public Health Lab for referral to CARPHA

– Lab request forms should be appropriately filled out

• Samples are subjected to an algorithm to rule out other prevalent arboviruses

• Turn-around time ~ 5 (working) days


Summary of results from Arboviral Algorithm (to Mid-February)

34

12

166

15

100

0

120

0

147

13

112

6 0

20

40

60

80

100

120

140

160

180

Tested Positive Tested Positive

Jan Feb

Results from Algorithm for PCR Testing for DENV CHIKV ZIKV

DENV CHIKV ZIKV


Dengue PCR breakdown

Den I 17%

Den II 8%

Den III 33%

Den IV 42%

January Dengue PCR

Den III 53%

Den IV 47%

February Dengue PCR


Feedback from Laboratory

• Need to reinforce completion of lab request forms – but vast

improvements noted over previous outbreaks

• Volume of requests affects turnaround time

– Large numbers of samples sent at height of outbreak investigation

needs to be reviewed. More judicious filtering needed in some

instances

• Testing window starts counting from day of onset as day 1

– (e.g. if fever or rash started on a Saturday, that would be is day 1 and

the last day on which a sample could be taken would be the following

Wednesday)


MONITORING POTENTIAL

NEUROLOGICAL SEQUELAE


The Cause for Concern

• In Late 2015 Brazil announced an unusual increase in Microcephaly cases in

areas hard-hit by ZIKV

• Initially > 3500 cases of microcephaly were identified, raising the incidence rate

by a factor of ~ 20

• Subsequent review of the data revealed

– >3000 cases were misclassified and discarded leaving ~ 500+ Microcephaly

cases

– Baseline data on Microcephaly may have been under-ascertained initially

– Even the more modest increase is a cause for precautionary measures,

however and WHO declared the phenomenon a PHEIC in February

• There has also been a noted increase in Guillain Barre Syndrome in other

States affected by ZIKV


ZIKV: - Potential Neurological Sequelae

• Surveillance for potential Neurological Sequelae of ZIKV

– Monitoring Microcephaly

• Member States encouraged to strengthen or develop developmental anomaly registries

• Standardised criteria are needed.

– Proportionality criterion - Head circ = [((length/2)+10)±2] is useful as an initial flag

» See table on following slide

– Need for consultation with Specialist Stakeholders – Virtual meeting?

– Pilot database under construction for use in country and for data submission to CARPHA

– GBS Surveillance

• Standardised case definition needs to be employed for ascertainment

– Use and expansion of AFP system?

– Development of New reporting channel?

• There is need to prepare health systems to deal with potential surges of GBS

• CARPHA is refining tools to facilitate reporting and collation of data on both GBS and Microcephaly in Member

States


Sample Table – Head circ. flagged according to

proportionality criteria

Case Head Circ

(cm) Length

(cm)

Lower

Proportionalit

y Criterion

Upper

Proportionalit

y Criterion Weight

(kg)

Head

Circ

Centile Height

Centile Weight

Centile

Actual 1 31.75 48.3 32.15 36.15 2.83 <3 15 15

Actual 2 35 51 33.5 37.5 3.21 85 85 50

Actual 3 35.5 53 34.5 38.5 3.36 85 85-97 50

Actual 4 34.5 51 33.5 37.5 3.31 50-85 85 50

Actual 5 35 57.5 36.75 40.75 3.84 85 >97 85

Fictional

1 37.5 50 33 37

Microcephaly

Normal Head Size

Macrocephaly

NB Head circumference is also generally proportionate to other foetal

measurements in terms of percentiles. Comparisons along these lines can also

be made


Photo credit: Image provided by mother of newborn (Rio de Janeiro,

Brazil), with authorization for dissemination exclusively among public

health workers.

First reports in Brazil: Unusual increase of newborns with microcephaly


AUTHORIZED PHOTOS OF CHILDREN WITH MICROCEPHALY. METROPOLITAN REGION OF RECIFE, 01/08 THROUGH 31/10/2015.

Microcephaly cases


CARPHA’s Advice to Pregnant Women

• CARPHA recommends that women of childbearing age living in

ZIKA affected take all preventive measures to avoid being

bitten by mosquitoes, which in addition to Zika can also

transmit diseases such as dengue and chikungunya.

• Women who believe they have been exposed to Zika virus

should consult with their healthcare provider for close

monitoring of their pregnancy.


Zika and Pregnancy

• Association between ZIKV infection and congenital anomalies including

Microcephaly is still under investigation

• Precautionary principle is being applied:

– WHO PHEIC

– Close follow-up of pregnant women who manifest symptoms of ZIKA

• Questions on ethics of active screening in pregnancy do need

consideration

– What actions will be considered after a positive diagnosis of ZIKV?

– What actions will be considered if constrained brain growth is

discovered?

– What actions are permissible within our legal frameworks?


Preventive measures

Personal preventive measures:

• The best way to prevent Zika is to avoid being bitten by mosquitoes. CARPHA advises

that you take proper precautions to prevent being bitten:

– Use insect repellants containing DEET (>10%), picaridin, oil of lemon eucalyptus or

IR3535 on exposed skin.

• Re-apply in accordance with instructions

– Wear long-sleeved shirts and long pants.

– Use air conditioning or have windows/doors securely closed or screened when

indoors.

– Sleep under mosquito nets.

Environmental Preventive Measures

• Identify and eliminate breeding sites in and around homes

• Cooperate with activities of local Vector Control Agencies


Conclusions

• Zika is likely to continue its spread through the Caribbean region

• Vigilance is advised, to detect index cases and heighten vector control

activities

• All persons are advised to employ both environmental and personal

strategies to reduce the risk of being bitten

• Pregnant women are advised to take special care to avoid mosquito

bites and to report any symptoms suggestive of ZIKV to their

obstetrician/doctors

• Surveillance for neurological sequelae needs to be established

• Preparations for surges in GBS in member states are needed

Zika Virus Surveillance and Reporting in the Caribbean

Health & Medicine