Covid 19 - Epidemiology and Prevention

COVID 19 - Epidemiology and Prevention

1. COVID -19
Epidemiology & Prevention
DrRohitKallukadavil
MBBS, MD, DNB, MRCP Sce(Resp)
Consultant Pulmonologist and Critical care specialist
HGM Hospital, Kottayam, Kerala.

2. Introduction…
•COVID-19iscausedbyanovelbetacoronavirus,nownamedSARS-
CoV-2.
•is theseventhCoronavirusknowntoinfecthumans.
•WasdeclaredaglobalpandemicbyWHOonMarch11th2020.
•Till now there is no specific treatment or vaccinations are available.

3. •Corona virus –can infect humans and animals(cats, bats,
cattles)
•Humans it can cause disease –common cold to
ARDS(SARS,MERS)
•Human infections are -αand βcorona viruses.

4. Introduction
•7 strains can infect humans
1.229E (αcoronavirus)
2.NL63 (αcoronavirus)
3.OC43 (βcoronavirus)
4.HKU1 (βcoronavirus)
5.SARS-CoV(the βcoronavirus that causes severe acute respiratory syndrome, or SARS)-2003
6.MERS-CoV(the βcoronavirus that causes Middle East Respiratory Syndrome, or MERS)-2012
7.SARS-CoV-2 (the novel coronavirus that causes coronavirus disease 2019, or COVID-19)-2019

5. •Virus causing COVID -1 9 is -severe acute respiratory
syndrome corona virus 2 (SARS-CoV-2), before: 2019-nCoV.

6. Origin ?
•SARS-CoV infected civet cats and infected humans in 2002
•MERS-CoV is found in camels and infected humans in 2012

7. Site of origin?
•Wuhan city of China

8. Wuhan Virology Lab ?

9. TransmissionofCOVID-19
•TheprimaryrouteforthespreadofCOVID-19isthoughttobethrough
aerosolizeddroplets
•Expelledduringcoughing,sneezing,orbreathing,
•alsoconcernsaboutpossibleairbornetransmission.
•Faeco-oraltransmissionhasalsobeenreportedinafewcases,withviral
isolationfromthefaecesofsomepatients

10. Transmission
•Droplets –viruses in respiratory
secretions when cough, sneeze,
talks
•Cough-3000 droplets
•Sneeze-40000 droplets
•Droplets travel –nearly 2 m/ 6
feets
•Droplets can enter through
respiratory mucous membranes

11. •Fomites–infected surfaces
•Infection can also occur by touching infected surfaces
followed by eyes, nose, mouth,

12. Persistence of Virus on surfaces
ObjectDuration
Gloves8 hours
wood 4 days
steel 2 days
glass 4 days
paper 5 days
Plastic 5 days
Surfaces disinfection
>60% Ethanol
0.5%Hydrogen peroxide solution
0.1%Sodium hypochlorite solution

13. Epidemiology

14. Jan 30-First case in Kerala /India
22/4/20-World: 25 L / 1.7 L deaths
India: 19,984/ 640
Kerala 408/3.

16. Epidemiology
Total cases: 24.3 L, Total deaths: 1.67 L (April 20th)

17. Affected countries

18. India
17,656 cases, 559 deaths

19. Kerala
Total: 408 cases, deaths: 3

21. Clinical features
•Incubation period-2 to 14 days, usually 5 days after
exposure
•Case fatality 2.3 to 5%
•More in elderly and males
•80%-mild to moderate disease
•13%-severe(Hypoxia, ARDS)
•6%-critical illness(shock, resp failure, MODS)

22. Symptoms
•ClinicalfeaturesasperChinesestudies
were
•Fever(83-98%),
•Drycough(59-82%)*,
•Fatigue(44-70%),
•Anorexia(40-84%),
•SOB(31-41%)
•Sputumproduction(28-33%),
•Myalgia(11-35%)and
•Lesscommonsymptomsweresore
throat,diarrhoea,dizziness,anosmiaor
ageusiain<10%pts.

24. COVID-19 Vs. FLU Vs. COLD

26. Definitions
•Confirmed case: A person with laboratory confirmation of
COVID-19 infection, irrespective of clinical signs and symptoms.
•Probable case: a suspected case with Test result inconclusive
or testing could not be done
•Covid Suspect:
•A pt with ARI & h/o travel to a location with community
transmission during 14 days prior to symptom onset.
•Or pt with ARI & close contact with COVID pt in last 14 days
•Or a pt with severe ARI in absence of alternative diagnosis

27. Close contact
•Face-to-face contact with a probable or confirmed case
within 1 meter and for more than 15 minutes
•Direct physical contact with a probable or confirmed case
•Direct care for a patient with probable or confirmed COVID-
19 disease without using proper personal protective
equipment

28. Lab findings
•Leucopenia and lymphopenia. Leucocytosis <25%
•Neutrophil/lymphocyte ratio if >3.1-predicts ARDS progression
•PLC can decrease
•SGOT/PT increase
•CRP elevated in 60-86%
•Ferritin elevated (? HLH)
•CXR: Normal –initially, then lobar multilobar consolidation
•CT: ground glass opacities with sub pleural distribution in lower
lobes –in early stages, then crazy paving, consolidations can
worsen

29. Prevention

30. Infectivity of Covid19
R0-average number of people
that will be infected from a
contagious person.
R0-is not fixed –decreases
with preventive measures.
Common Influenza-1.3

31. For community

33. How to prevent community transmission
•Lock down, avoid
crowds
•Closure of non
essential services
•Closure of schools
•6 F –social distancing
•Hand hygeine

34. Non pharmacological interventions to reduce COVID
mortality-Model by Ferguson et al

35. Social distancing saves lives….

36. •Quarantine-separation of individuals who are not yet ill
but have been exposed to COVID-19, have a potential to
become ill.
•Isolation-separation of individuals who are ill, suspected,
or confirmed COVID-19 cases.

37. •During SARS outbreak in 2003 found that washing hands
more than 10 times daily was 55 percent effective in
stopping virus transmission
•while wearing a mask was actually more effective at about
68 percent.
•Hand washing+ Mask+ Gloves –91% protection.

38. Data -13/4/20

39. Iceland
•No lock down
•1778 cases with 10 deaths, 1417-recovered
•Banned crowds>20 people
•Closed schools.
•Mainly by Testing and contact tracing
•50% of population-testing(3.5 L-total population)

40. How China controlled COVID ?
•? Reliable data
•11 weeks lock down in Wuhan
•Two specialist corona hospitals in Wuhan
•Strict containment measures.
•AI, mobile app(WeChat) for contact
tracing and travel restriction.
•Availability of PPE, masks etc.
•?Previous experience with SARS-in
2002(5000 cases/ 500 deaths)

43. •Health care workers are the most important agents in the
fight against COVID -19
•Everything else could be manufactured

44. Hospitals act as amplifying centres for the epidemic
•Hospitals act as amplifying centres for the epidemic-during
SARS and MERS epidemics.
•-need to reduce crowd in hospitals
•-less severe COVID cases should be treated in home or
specific covid care centre.

45. Clinical practice-precautions..
•Doctorsandparamedicalstaffaboveageof60 years.
•Thosewithunderlyingmedicalconditions(especially
immunocompromised/predisposingtoinfections)like: –DM,
CLD,CKD,CAD,ChroniclungconditionslikeAsthma,COPD,
Bronchectasis,ILD,etc.,Cancer,OnChemotherapyorSteroid
treatment,Pregnant,Seropositivestatus.
•Always consider –every patients as Corona suspect-unless
proved otherwise.
•Always use Mask and Hand hygiene

46. Triageonphone
•Thecrucial1ststepinprotectingdoctorsandotherpatients.
•AllpatientsmustbeassessedforpossibleCOVID-19infection.
•Askforcontactortravelhistory-beforeappointment-atregistrationarea.
•IfanypatientseemstobeCovidsuspect,pleasereferhimtothenearby
Covidtestingcentre.
•Avoidroutinefollowups,electiveprocedures
•Guidethepatientonphoneforminorissuesatyourdiscretion

47. Triageatclinic/Hospital,ifpossible…
•PatientswithFever,coughordyspnoeashouldbeevaluatedina
separatearea-?Feverclinic
•Triagestationswithadequatelytrainedstaffshouldbeallottedatthe
entranceofeachhealthcarefacility.
•GiveTripplelayermasktosuspectedpt.
•Keep1meterdistancefrompt.
•Allotdedicatedequipmentslikesteth,glovesetc.
•UseofPersonalProtectiveEquipments(PPE)ispreferred.
•Performhandhygeine.

48. Clinicmanagement…
•Restrict the OPD time to limited hours
•Avoid walk-in patients
•Avoid relatives in OPD as much as possible
•Make the patients sit about 1 meter apart
•Keep windows and doors open
•Avoid A/c
•If patient need to be examined on bed or table, clean it immediately
following the examination.

49. Clinicmanagement…
•Thedoctorshouldwearasurgicalmaskandscrubhandswithsoapandwateranduseanalcohol-
baseddisinfectantaftereachpatientinteraction.
•Minimizefomitesontableorinclinic-includingcurtains,mobilesetc.
•AvoidmultiplestaffattendingOPD,allotdedicatedstafftoeachOPD.
•Keepwaitingroomchairsplaced6feetapart.
Decontamination:
•1.Hightouchsurfaces:Disinfectionofhightouchsurfaceslike(doorknobs,telephone,callbells,
bedrails,stairrails,lightswitches,wallareasaroundthetoilet)shouldbedoneevery3-4hours.
•2.Low-touchsurfaces:ForLow-touchsurfaces(walls,mirrors,etc.)moppingshouldbedoneat
leastoncedaily.

50. Displayin Clinics…
•Visualalertsshouldbepostedattheentranceandstrategicareas
(waitingareas,elevatorsandcafeterias)
•Toreinforcebothpatientsandhealthcareworkers,theimportance
ofhandhygiene,respiratoryhygieneandcoughetiquette

51. Handhygiene…
•Allhealthcareworkersshouldperformhandhygieneusingalcohol-basedhand
rub(20s)orbywashingwithsoapandwater(minimum40seconds).
•Ifhandsarevisiblysoiled,usesoapandwaterforhandwash.
•Avoidtouchingfacemask,eyes,nose,facebeforehandwashing.
•Footoperatedsanitizersshouldbeputoutsideelevators,OPDs,screening
areas,ICUsandwards.
•Sanitizefollowing:Computerkeyboardandmouse,Houseandcarkeys,Re-usable
waterbottles,Carsteeringwheel,Doorhandles

53. How hand hygiene works ?
•Water helps in rinse of nanoparticles like dirt
and viruses out of crevices which make up our
finger prints
•COVID has lipid membrane-damaged with soap
molecules.
•Hydrophobic tail bond with viruses and dirt and
hydrophilic part bond with water and get
washed away.
•Alcohol break the lipid membrane

54. Needoftheprotectivegearsforall?
•Handhygieneisforallhealthcareworkers
•Baseduponyourroleinpatientmanagementanddurationof
exposurewithpatient(morethanorlessthan15minutes),youhave
todonntheprotectivegears.
•Thus,needofprotectivegearsdependsupontheplacewhereyouare
practicing

55. •Aerosol generating procedure-Intubation, suctioning,NIV,
CPR, Bronchoscopy, Neb, specimen collection) –Use full PPE
with N95 mask.
•COVID ICU,OT,Ward –Full PPE with N95
•Non covid ward-3 ply surgical mask
•All other areas of hospital-with less chance of COVID-use 3
ply mask.

56. Mask
American standard –by NIOSH –N 95%
Europestandrad-FFP2-Filtering face piece score 2

57. Masketiquette…
Increaseinriskoftransmissionassociatedwiththeincorrectuseanddisposalof
masks.
i.Placemaskcarefullytocovermouthandnoseandtiesecurelytominimizeanygaps
betweenthefaceandthemask
ii.Whileinuse,avoidtouchingthemask
iii.Removethemaskbyusingappropriatetechnique(i.e.donottouchthefrontbutremove
thelacefrombehind)
iv.Afterremovalorwheneveryouinadvertentlytouchausedmask,cleanhandsbyusingan
alcohol-basedhandrubfor20secondsorsoapandwaterifvisiblysoiledfor40seconds
v.Replacemaskswithanewoneassoonastheybecomedamp/humid
vi.Donotre-usesingle-usemasks
vii.Discardsingle-usemasksaftereachuseanddispose-offthemimmediatelyuponremoval
viii.ForN95respirators(can use for 8 Hr)-fitcheckmustbeperformedafterwearing.

60. TRANSPORTPROTOCOL
ForshiftinganysuspectedorconfirmedCOVID-19patients,thefollowingsteps
mustbefollowedbytheaccompanyinghealthcareprovider:
A.Decontaminatehands(alcohol-basedsanitiser/soap)
B.DonPPE
C.InformTraumaCentrecontrolroomregardingtheadmission/transfer
ofapotentiallyinfectiouspatient.
D.Inambulance
•Usesingleuseorsinglepatientusemedicalequipmentwherepossible
•Usedisposablelinenifavailable
•Monitoranddocumentvitalsandmedicalmanagementdonein
ambulance

61. Environmentalsanitation:
•Immediatelyremoveandwashclothesandbeddingthathaveblood,stoolorother
bodyfluidsonthem
•Cleananddisinfectfrequentlytouchedsurfacesinthequarantinedperson’sroom
(e.g.bedframes,tablesetc.)dailywithSodiumHypochloritesolution(1%)or
ordinarybleach(5%)
•Cleananddisinfecttoiletsurfacesdailywithregularhouseholdbleach
solution/phenolicdisinfectants
•Washlaundryusedbythepersonseparatelyusingcommonhouseholddetergent
anddrythoroughly
•Placealluseddisposablegloves,masksandothercontaminatedwasteinalined
containerbeforedisposing

62. Special precautions to be followed for aerosol generating
procedures
•Includetrachealintubation,non-invasiveventilation,tracheostomy,
cardiopulmonaryresuscitation,andbronchoscopy.
•Areallassociatedwithincreasedriskoftransmissionof
•COVID-19
•HCWsconductingsuchproceduresshouldbewearingfull-bodyPPEs
includingN95particle-filteringmasks
•Shouldbecarriedoutinanadequatelyventilatedroomorinairborne
infectionisolationrooms(AIIR)whicharenegativepressurerooms

63. EmotionalneedsofHCWs
•Must not be ignored
•HCW at front-line are under extreme physical and mental stress.
•They are physically overworked, forced to make tormenting triage
decisions, upset by guilt and pain from losing patients and colleagues.
•Worrying about their own health and the constant anxiety of passing
infection on to their families.
•China-70% stress, 50% depression, 44% anxiety, 34% insomnia.

64. Forallmedicalprofessionals(Important points…)
Socialdistancingpoorlypracticedinhospitals,sopleasepayattention
•Keep1mdistance always
•Noelectivejobathospital
•Cleanyourdesk,doorknob,computer,workstationyourselforinyourpresence
•Keepdooropens
•Minimaltouching
•Donottouchpapersandfiles,preferElectronicentries,iffeasible
•Washhandsaftereverypatientexaminationandcleanyourinstruments with
sterilium,especiallystethoscopetoavoidcrossinfection
•Avoid lifts, Closed space, Don’t touch lift buttons. Get them cleaned often
•AvoidHeavyloadatclinic
•Leaveallyourstethoscope,kneehammersandothermedicalstuffinhospital
itself.Don'ttakehome
•Decontaminatecarhandles

65. •Useonly1pen,phoneandwaterbottle(disposablebetter)
•Decontaminatephone
•Nowatchesnoringsnobanglesnodanglingearrings
•HairstiedandCoveryourheadwithcap.
•Shifttoscrubsfullsleeves,ifavailable.
•EmptybowelandbladderbeforeyouwearyourPPE
•Weardoubleglove, goggle, foot covers
•Keepyourpalmstogetherwhenyouseepatientstoremindyounotto
touchthem.
•Better don'tusestethoscope.Thesearenotnormaltimes
While on PPE (Improtantpoints…)

66. Boost your Immunity
•Good food, plenty of oral fluid intakes, fruits and vegetables
•Sleep-7-8 hours
•Regular exercise
•Vaccinations ????

67. ICMR recommendation for COVID-19 Use of
hydroxy-chloroquinefor prophylaxis for selected individuals as follows
•Asymptomatic healthcare workers involved in the care of
suspected or confirmed cases of COVID-19:
–400 mg BD-Day 1, then 400 mg once weekly x next 7 weeks
•Asymptomatic household contacts
–400 mg BD -Day 1, then 400 mg once weekly for x 3 weeks
Contraindications: QTc>500msec, Porphyria, Myasthenia, Retinopathy, Epilepsy.

68. Evidence
•Cause Increase Ph of endosome and prevents virus entry,
transport and post entry events ?
•invitro action-chloroquine/ hcq against viruses-corona/
influenzea
•No peer reviewed publications/ well conducted RCT.
•Unpublished study from China and France(HCQ+
Azithromycin) –showed better viral clearance.

69. Thank you