This slide presentation was delivered by the Ministry of Health at a sensitization session for health professionals in Belize City. The debilitating disease first detected in the Caribbean in November 2013 is suspected to have affected more than 10,000 in 11 countries.

2. CHIKUNGUNYA FEVER
Objectives
• Historical epidemiology of CHIKUNGUNYA
• Regional scenario
• What is CHKV
• Clinical presentation
• Vector borne diseases, Differential Diagnosis, Transmission
• At risk groups ,Dengue /CHIKV dengue snapshot
• Treatment
Francis Morey MD.MPH
Lorna Perez Surveillance Officer Epi-Unit

3. History (Its story)
A viral infection transmitted to humans
By the bite of an infected mosquito
It has become endemic in south and central
India
First outbreak in 1952 on the Makonde Plateau
Border between Tanganyika and Mozambique
First published report is from Africa in 1955 by
Marion Robinson and W.H.R. Lumsden
Recent large epidemic occurred in Malaysia in
1999 www.drsarma.in 3

4. A disease of Africa and Asia
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5. INTRODUCTION
 Caused by an Alpha Virus is a relatively rare form of viral
fever ("debilitating non-fatal viral illness."
 Spread by bite of Aedes aegypti mosquito which usually bite
during day light hours.
 the name is derived from Swahili word meaning “that which
bends up”
 Chikungunya (CHIK) virus first isolated from the serum of a
febrile human in Tanzania in 1953.
 Chik virus has caused numerous out breaks in Africa and
South Eastern Asia, involving hundreds and thousands of
people.

6. • Chikungunya is a
Makonde word (one of
the local languages in
Tanzania) meaning
‘that which bends up’.
• Describes the posture
patient assumes to
relieve the severe joint
pains
• Buggy Creek virus

7. Synonyms
• CHIKV Fever
• Buggy Creek virus infection
• Knuckle fever
• Me Tri virus infection
• Semliki Forest virus infection
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8. The Recent Epidemics
8
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9. 9
195
4
200
4
200
6
African profile Asian profile
Current global profile
A226V-CHIKV
Humans
Peridomestic mosquitoes
Ae.aegypti
Ae.albopictus

Focal urban outbreaks
Wild primates
Forest
dwelling mosquitoes
Ae. furcifer
Ae. taylori…
Humans

Sporadic cases
Focal urban outbreaks
Humans
Peridomestic mosquitoes
Ae. albopictus
Ae.aegypti

Massive urban outbreaks
Simon F et al. Curr Infect Dis Rep 2011 (in press)

10. Notable Outbreaks
1963 to 1965 - An epidemic was reported in Calcutta –
4.37% of the people were later found to be seropositive
1973 – An epidemic 37.53% in Barsi - Sholapur district
2006 – Present epidemic after 33 years is the largest
9,06,360 or more cases in Andhra Pradesh
5,43,286 cases from Karnataka; 66,109 from B’lore
Maharashtra 2,02,114 cases; Gujarat 2,500 cases
Tamil Nadu 49,567 cases; Orissa 4,904 cases,
Madhya Pradesh 43,784 and Pune 138 cases
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11. Most Recent Epidemics
• Epidemic of CHIKV occurred in Malaysia – 1999
• French island of Réunion in the Indian Ocean- 2005
• Epidemic was recorded in Mauritius – 2005
• Madagascar, Mayotte and Seychelles – 2005
• Hong Kong and Malaysia early 2006
• Present indian epidemic is the largest -from Dec ’05
• Maximum # of cases from Andhra Pradesh so far
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12. 12
Chikungunya, 2005-2012, more than
three millions cases ?
South of France, 09/2010
2 autochtonous cases
New Caledonia, 03/2011
33 autochtonous cases
Yemen - Saudi
Arabia, 2010-11
Hundreds of cases
South China, 10/2010
>10 cases
Reunion, 2010
120 cases

13. www.drsarma.in 13

14. Why is this sudden epidemic ?
Analysis of the recent Indian epidemic has
suggested that the increased severity of the
disease is due to a change in the genetic
sequence, altering the virus’ coat protein,
which potentially allows it to multiply more
easily in mosquito cells*.
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*http//medicine.plosjournals.org

15. Why is this quasi-pandemic ?
• Several distinct variants of the virus
• A change at position 226 of the E1 coat protein
• This A226V mutation caused the virus to more easily
invade and multiply in the mosquitoes
• Three protein changes in non-structural proteins
– nsP1 (T301I), nsP2 (Y642N), and nsP3 (E460 deletion)
– This mutant virus - from a neonatal encephalopathy
case
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16. Regional scenario
16

18. CHIKUNGUNYA
The MOH/PAHO Belize request your Boarding pass

19. The CHIK Virus
19
www.drsarma.in

20. What is this virus ?
• Causative agent is an RNA – VIRUS
• Class – Arbor Virus (Arthropod Borne)
• Family – Togaviridae
• Genus – Alpha Virus
• Species – Chikungunya Virus
• Similar to Semliki Forest Viruses (SFV) in Africa
and Asia.
www.drsarma.in 20

21. Epidemiological Triangle
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The HostThe Virus
The Environment
Interaction
The Vector

22. Vector Borne diseases
• Mosquitoes
• Aedes
– Dengue fever
– Rift Valley fever
– Yellow fever
– Chikungunya
• Anopheles
– Malaria
• Culex
– Japanese encephalitis
– Lymphatic filariasis
– West Nile fever
• Sandflies
• Leishmaniasis
• Sandfly fever (phelebotomus fever)
• Ticks
• Crimean-Congo haemorrhagic fever
• Lyme disease
• Relapsing fever (borreliosis)
• Rickettsial diseases (spotted fever and Q fever)
• Tick-borne encephalitis
• Tularaemia
• Triatomine bugs
• Chagas disease (American trypanosomiasis)
• Tsetse flies
• Sleeping sickness (African trypanosomiasis)
• Fleas
• Plague (transmitted by fleas from rats to humans)
• Rickettsiosis
• Black flies
• Onchocerciasis (river blindness)
• Aquatic snails
• Schistosomiasis (bilharziasis

23. Arbovirus (arthropod-borne virus) applies to any virus that is transmitted to humans and/or other
vertebrates by certain species of blood-feeding arthropods, chiefly insects (flies and mosquitoes)
and arachnids (ticks)
• Bunyaviridae (comprising the bunyaviruses, phleboviruses, nairoviruses, and hantaviruses)
• Flaviviridae (comprising only the flaviviruses)
• Reoviridae (comprising the coltiviruses and orbiviruses)
• Togaviridae (comprising the alphavirus)

24. Fever, malaise, headaches, myalgias
Additional features: none Colorado tick fever Reoviridae (Coltivirus) Ticks
Dermacentor sp
Western US, western
Canada
Phlebotomus fever Bunyaviridae (Phlebovirus) Sand flies
Phlebotomus sp
Mediterranean basin,
Balkans, Middle East,
Pakistan, India, China,
eastern Africa, Panama,
Brazil
Venezuelan equine
encephalitis
Togaviridae (Alphavirus) Mosquitoes
Culex sp
Argentina, Brazil, northern
South America, Panama,
Mexico, Florida
Lymphadenopathy, rash Dengue fever Flaviviridae Mosquitoes
Aedes sp
Southeast Asia, West Africa,
Oceania, Australia, South
America, Mexico,
Caribbean, US
West Nile fever Flaviviridae Mosquitoes
Culex sp
Africa, Middle East,
southern France, Russia,
India, Indonesia, US
Arthralgia, rash Chikungunya disease Togaviridae (Alphavirus) Mosquitoes
Aedes sp
Africa, India, Guam,
Southeast Asia, New
Guinea, limited areas of
Europe
Mayaro virus Togaviridae (Alphavirus) Mosquitoes
Haemogus sp
Brazil, Bolivia, Trinidad

25. Hemorrhagic signs‡
Yellow fever Flaviviridae Mosquitoes
Aedes spp
Central and South
America, Africa
Dengue hemorrhagic
fever
Flaviviridae Mosquitoes
Aedes sp
Southeast Asia, West
Africa, Oceania,
Caribbean
Machupo virus Arenaviridae Rodent Bolivia
Junin virus Arenaviridae Rodent Argentina
Guanarito virus Arenaviridae Rodent Venezuela

26. Fever and CNS involvement
Eastern equine
encephalitis
Togaviridae (Alphavirus) Mosquitoes
Culex sp
Atlantic and Gulf coasts
of US, Caribbean, upper
New York, western
Michigan
Western equine
encephalitis
Togaviridae (Alphavirus) Mosquito US, Canada, Central and
South America
West Nile virus Flaviviridae Mosquitoes
Culex sp
Africa, Middle East,
southern France, former
Soviet Union, India,
Indonesia, US
St. Louis encephalitis Flaviviridae Mosquitoes
Culex sp
US, Caribbean
Venezuelan equine
encephalitis
Togaviridae (Alphavirus) Mosquitoes
Culex sp
Argentina, Brazil,
northern South America,
Panama, Mexico, Florida
La Crosse encephalitis Bunyaviridae Mosquitoes
Aedes spp.
North Central States,
New York

27. Transmission
Reservoir – Non-human primates in Africa
No animal reservoir is found in India
Maintained in nature by man – mosquito – man
cycle
Vector – Aedes aegypti, Ae. albapticus mosquito
Same vector as for Dengue and Yellow fevers
Vehicle of transmission – None
No known mode - other than mosquito bite
Incubation Period – 2 days to 12 days
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28. Main mode of transmission: mosquito bite
Other modes of transmission
• Uncommon
– In utero transmission, can cause miscarriage in the 1st
trimester
– Intra birth transmission, newborn of a viremic mother
– Needle prick
– Laboratory exposure
• Public Health Considerations
– Blood transfusion
– Organ or tissue transplant
– No evidence of the virus in breast milk
CHIKV in the Americas28

30. The Vector
Aedes aegypti mosquito, flight range < 100 meters
Aggressive daytime biter – under lights – bites ankles
Once infected – it has the virus until death (30 days)
It is a man made mosquito – prefers its owner
Breeds in man made household containers
Indoor, peridomestic, fresh water mosquito
Metallic, plastic, rubber, cement and earthen
containers - open, left or unused - get filled with water
Air coolers, ACs, Old oil drums, Over head tanks
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31. The Virus and its Vector
The Criminal and It’s Accomplice
How Do Aedes Mosquitoes Transmit Diseases...
Mosquito bites and sucks
blood containing the virus
from an infected person.
Virus is carried in its body.
And passes the virus
to healthy people
when it bites them.

32. Attack Rates
• In urban localities it is more – why ?
• Usual age group is above 15 years
• Less common in children and infants
• Family clustering of cases usual
• Attack rates vary from 3 to 40% of population
• Average attack rate is 10%
• Herd immunity restricts further spread
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33. Aedes aegypti/albaptycus/Tiger mosquito
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34. Clinical Features
34
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35. CHIKV Infection
a disease of two phases
ACUTE PHASE
•The majority of persons infected (72% 97%)‒
are symptomatic.
•Incubation period: 3–7 days (range of 1 12‒
days).
•Main symptoms: acute onset of fever and
polyarthralgia.

36. CHIKV Infection
a disease of two phases
CHRONIC PHASE
• Early exacerbations,
inflammatory relapses,
longstanding rheumatism and
loss in quality of life
• More common in:
– Those over 40 years old
– Rheumatic or traumatic
history
– High viral load
Simon F et al. Chikungunya virus infecion. Curr Infect Dis Rep DOI 10.1007/s11908-011-0180-1

38. CLINICAL FEATURES
 Acute viral infection of abrupt onset.
 sudden onset of fever >38.5 degrees and severe
arthralgia( ankle ,wrist, phalanges). Chills, flu like symptoms.
 other constitutional symptoms like head ache, back pain,
myalgia,photo phobia, retrorbital pain, conjunctival infection
and rash. Nausea, vomiting, abd. pain, severe weakness
 Incubation period is usually 1 to 12 days, symptoms
( average 4-7days).
 Lasting for period of 7 to 10 days.
 Rarely can result in meningo – encephalitis,
Cardiovascular alt,death in elderly-weak immune system.
Chronic phase of severe arthralgia

39. Fever and polyarthralgia
• Fever
– Acute onset
– ≥38.5°C
• Joint pain
– Sometimes serious and debilitating
– Multiple joints
– Bilateral and symmetric (usually)
– Most commonly in hands and feet
http://www.paho.org/hq/index.php?option=com_docman&task=doc_download&gid=16985&Itemid=

40. Other signs and symptoms
• Headache
• Myalgia
• Arthritis
• Conjunctivitis
• Nausea and vomiting
• Maculopapular rash
http://wfffun.info/diseases/chikungunya-rash-photos-2/

41. 41
Subacute stage, persisting distal inflamatory arthralgias
Simon F et coll. Medicine 2007;86: 123-37

42. 42
Subacute stage, tenosynovitis

43. 43
Simon F et coll. Medicine 2007;86: 123-37
Subacute stage, bursitis

44. 44
Subacute stage, associated rheumatic disorders

45. 45
Simon et al. Medicine 2007; 86 (3)
Peripheral vascular disorders
• Erythermalgia
• Raynaud’s syndrome
– High susceptibilty to the cold
– De novo and transient
– Commonly bilateral
– Associated with mixed cryoglobulinemia

47. The Arthralgia
• The small joints of the lower and upper limbs
• Migratory poly arthralgia – not much effusions
• Larger joints may also be affected (knee, ankle)
• Pain worse in the morning – less by evening
• Joints may be swollen & painful to the touch
• Some patients have incapacitating joint pains
• Arthritis may last for weeks or months.
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48. Kun gunyala
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The Contorted Posture

49. Skin Rash in Dengue CHIKV
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51. Rare Clinical Features
• A petechial or maculo papular rash usually
involving the limbs may occur.
• Hemorrhage is rare
• Nasal blotchy erythema, freckle-like
pigmentation over centro-facial area,
• Flagellate pigmentation on face and extremities
• Lichenoid eruption and hyper pigmentation in
exposed areas
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52. Rare Clinical Features
Multiple aphthous-like ulcers over
scrotum, crural areas and axilla
Unilateral or bilateral lympoedema of the limbs
Lymphadenopathy not common
Multiple ecchymotic spots in children
Vesiculo-bullous lesions in infants and
Sub-ungual hemorrhages
Severe menigo-encephalitis – rare; may be
fatal
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53. Course of Illness
Fever typically lasts for 2 - 3 days and comes down
Fever may reoccur after 3 days – ‘saddle back’ fever
Some rare cases - fever lasts up to a couple of weeks
Patients do have prolonged fatigue for several weeks
High fever & crippling joint pain marked this epidemic
Joint pain, intense headache, insomnia and an extreme
degree of prostration may last for 5 to 7 days
Life long immunity, once one suffers this infection
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54. Who are at greater risk ?
• Pregnant women
• Elderly people
• Newborns
• Women in general
• Diabetics
• Immuno-compromised patients
• Patients with severe chronic illnesses
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55. CHIKV Morbidity
• Chikungunya is a self-limiting illness
• Causes of prolonged morbidity are
– Severe dehydration
– Electrolyte imbalance and
– Loss of glycemic control
• Recovery is the rule
• In about 3 to 5%
– Incidence of prolonged arthritis
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56. Mortality
• A few deaths have been reported - Examples
• It was thought to be due mainly to
– Inappropriate use of antibiotics and NSAIDs
– Virus can cause thrombocytopenia
– These drugs can cause gastric erosions - thus
– Leading to fatal upper GI bleed
– Use of steroids for the joint pains &
inflammation
– This is dangerous and completely unwarranted
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57. Outcome
• Acute symptoms: resolved in 7-10 days
• Mortality: rare (elderly)
• Some patients have relapses of rheumatic
symptoms in the months following the acute
illness
• Chronic illness of varying degrees, with pain
persisting for months or years
CHIKV in the Americas57

58. DIAGNOSIS
Suspect Case
 Characteristic triad of fever, rash and rheumatic
manifestations
Probable Case
 As above with positive serology from single sample
Confirmed Case
 A probable case with any of the following
 Four fold HI antibody difference in paired serum samples.
Detection of IgM antibodies.
 Virus isolation from serum.
 Detection of Chikungunya virus nucleic acid in sera by RT -
PCR

59. Laboratory
• Transient lymphopenia
• Thrombocytopenia (early and
moderate)
• C-reactive protein elevation
• Elevated liver
transaminases
Risk factors for severe disease
• Infant exposure during birth
• Elderly (>65 y.o.)
• Medical history (e.g., diabetes,
hypertension, or
cardiovascular disease)

60. WHO case definitions

61. Algorithm for suspected CHIKV CASE

62. Epidemiological scenario: First introduction of virus in a specific area 1
This algorithm is intended to be followed by those reference laboratories with established capacity for CHIKV
detection.
Samples should be processed taking into account the number of days after the onset of symptoms. If the sample
was taken between 1 and 8 days after the onset of symptoms, then it will be processed for both RT-PCR and IgM
serology.
Samples should be coming from suspected cases, defined as “A patient with acute onset of fever > 38.5 C (101.3 F)
and severe arthralgia or arthritis not explained by other medical conditions, and who resides or visit epidemic or
endemic areas within two weeks before the onset of the symptoms”.
2

63. Algorithm Dengue/CHIKV

65. Pregnancy and CHIKV
65
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66. Pregnancy and CHIKV
• Mother to fetus transmission can occur
• Reported between 3 to 4.5 months of gestation
• Maternal IgG develops in 2 weeks after CHIKV
• This passes through placenta – confers protection
• Intra-partum risk is 48% if mother has viremia
• Neonatal infections are very mild; fully recover
• No miscarriages or congenital malformations
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67. Pregnancy - CHIKV
June 2005 to Jan 2006, 84 pregnant women with
CHIKV
In 88% cases the newborns are asymptomatic
10 newborns had severe attacks, 4 meningo-
encephalitis
3 with intravascular coagulations; No infants died
One case of severe intra cerebral hemorrhage
Had severe thrombocytopenia
All confirmed by specific serology or PCR or both
Women had severe intra-partum viremia & feverwww.drsarma.in 67

68. Differential Diagnosis
• Dengue fever, DHF, DSS
• O’nyong-nyong viral fever
• Sindbis viral fever
• Other non specific viral fevers
• Any other acute fever like malaria, UTI etc.
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69. 69
MALARIA
DENGUE
FEVER
CHIKUNGUNYA FEVER
Jaundice
Renal failure
Fever
Myalgia
Rash
Bleedings
Retro-orbital pain
Transient arterial
hypotension
Acute polyarthritis
Tenosynovitis
Anemia
LEPTOSPIROSIS
Adapted from Simon et al, Schwartz, Infections in travelers, Ed 2009
BACTERIAL
SEPSIS
Myalgia
Myocarditis
ADRS
Chikungunya outbreak, high risk for misdiagnosis

70. Dengue and CHIK
• Virus transmitted by the same
mosquitos
• Similar clinical picture
• The viruses can circulate in the same
areas–- co-infection
• Discarding dengue is important, for an
adequate clinical care that improves
the prognosis of dengue

71. Differential Diagnosis
Feature CHIKV DENGUE
Presentation A+F ± mild rash A+F+Rash
Arthralgia Moderate Severe
Arthritis Not common Frequent
Bone pains None Break bone fever
Thrombocytopenia Mild (Not < 1K) May be severe
Hemorrhage None May be present
Shock syndrome Never May occur
Immunity (IgG) Life long 2nd
attack fatality
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72. Table 1: Total number of Febrile cases positive for Dengue per District for 2014
District Confirmed probable clinical Suspected Total
WHO case
definition
% dengue of
febrile cases
% District
febrile cases
Corozal 3 5 7 76 91 15 16.5 11.0
Orange Walk 0 1 0 13 14 1 7.1 1.7
Belize 9 16 22 346 393 47 12.0 47.4
Cayo 8 6 6 142 162 20 12.3 19.5
Stann Creek 6 3 2 87 98 11 11.2 11.8
Toledo 6 0 1 63 70 7 10.0 8.4
Unknown 0 0 0 1 1 0 0.0 0.1
Total 32 31 38 728 829 101 12.2 100.0

73. Laboratory description of Dengue Test
Test description Rapid test requested Eliza test Requested Total percent
Test requested 644 282 926 100.0
Test Done 622 242 864 93.3
RESULTS IgM positives NS1 positives Total IgM/NS pos
Total positive test 32 40 72 100.0
positivity rate % 5.1 16.5 8.3 91.7 negative

74. Treatment of CHIKV
74
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75. CHIKUNGUNYA DRUG
France develops a new drug to treat
"We are confident today that a drug to treat
Chikungunya will be made available and we
are hopeful that this drug will be available at
the very end of this year or at the very start
of 2007"
- French Health Minister - Xavier Bertrand
- September 11th
2006
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76. Treatment
• There is no specific treatment for CHIKV
• No vaccine or preventive pill is available
• The illness is usually self-limiting
• It will resolve with time over a week to 10
days
• No relapses occur – no second attacks
• Convalescence may take longer
• Symptomatic treatment only
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77. Treatment
Rest to the patient and mild movements of joints
Cold compresses to inflamed joints
Liberal fluid intake or IV fluids
Analgesics and NSAIDS
Paraetamol ± Ibuprofen or aceclofenac or
diclofenac
Naproxen sodium (Naprasyn, Xenobid)
Aspirin should be avoided
Hydroxy chloroquine sulphate (HCQS) 200 mg/od
Chloroquine phosphate 250 mg/odwww.drsarma.in 77

78. What not to give ?
• No indication for antibiotics
• Never use costly, large spectrum drugs
• No indication for long acting steroids
• No indication for short term steroids also
in the acute phase of illness
• Rarely, if the joint swelling persists – we
may consider use of steroids in short
burst.
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79. Management of cases
• Rest in bed will help hasten recovery
• Infected persons should be protected
– from further mosquito exposure
– staying indoors and/or under a mosquito net
– during the first few days of illness
– This is to reduce transmission to others
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80. The Virus and its Vector
The Criminal and It’s Accomplice

81. CHIKUNGUNYA