·
Community-group
of people living in the same place or having a particular characteristic is common.
·
Epidemiology_
a branch of science which deal with incidence, distribution and possible Control
of disease and other factor related to
health
·
Epidemiological
triad-Agent, host ,environment
·
Host-A
person or other animal that provide the place to an infectious agent under natural condition
·
Obligate host-only
men is host .E g. Measles, typhoid
·
source-person
,animal ,object, substance that passes the infectious agent
·
Reservoir-Any
person, object ,animal, In which infectious
agent lives or multiplies for its Survival
called reservoir
·
Source and
reservoir not same e g. .Hook
warm-source-dust and soil , reservoir
·
case are types(i)clinical(ii)subclinical(iii)latent
·
Clinical
case appearent active, mild, moderate ,typical, ,severe and fatal
important Source of infection than severe case because they are abudent & spread the infection Wherever they go
·
Subclinical
case in appearent , dormant , covered, missed ,or ,abortive case. In which disease agent lives
,multiplying or grow but doesn’t show sign
and symptoms it self. These type of case
Only detect by lab. Investigation.
·
Latent case-it Is a inactive, dormant , due to Immunity, infection
hide which demonstrable presence in blood, tissue
,or body secretion of the host. (sign& symptom show after
decrease Immunity, but subclinical never show s & s)
·
First case
of communicable disease introduced into
the population unit being studied is called Primary case.(first case in the
investigation of the outbreak of a potential epidemic disease)
·
Secondary case-that develop contact with primary case
·
Index case
first case to come to the attention
of investigator .It is not always a primary case (first case that indicates existence
of outbreak)
·
Infection transmitted
by direct contact from skin to skin , mucosa to mucosa, mucosa to skin, Is called direct contact transmission
of disease.
·
Droplet transmission – droplet of saliva & naso-pharyngel secretion during coughing ,sneezing ,speaking &
spitting in to surrounding atmosphere . ( partical more than 10 mm. Filtered by the nasal mucosa less
than 5 mm. can penetrate deeply in alveoli and other tissue)
·
Transmission
of infection though placenta to new born is called vertical transmission Or trans-placental.
·
Indirect
transmission of disease occur by 5f's (flies , finger , fomites ,food, & fluid) transmission.
·
Termination
of complete transmission of infection by
extermination of the infectious agent Through surveillance & containment called
Eradication.
· Surveillance continues scrutiny
of the factor that determine the occurance & distribution of Disease or other conditions of illness .It essential for prevention
& control of disease.
· A methods for identifying the missing case & there
by requirement for supplementing the notified case is called sentinel surveillance.
· The period between exposure to an infection & the
appearance of first sign and symptoms of disease is called incubation period.
·
Maximum
and pic level of sing and symptoms of disease Is called prodermal period.
·
Symptoms indicative
of an approaching disease Very dangerous
stage because patients Remain very contagious. Highest point of disease condition
with specific sign and symptoms called fastigium
stage.
·
Defervecence
stage-to become calm,subsidence of fever to a normal temperature.
·
Convalescence
stage prior of recovery after a disease.
·
Defection stage
is just like a converscence stage.
·
Latent period-the
period from disease initiation to disease detection
·
.
·
Generation
time,infectivity period is a interval of
time between recipient of infectious host And maximum infectivity of the
host.
·
Communicable
period-the time during which an infectious agent may be transfer directly Or indirectly
from an infected person to an animal including arthropods.
·
Lodgement and
development and multiplication of parasite on the surface of the body or in The
clothing called infestation.Ex.-Lice,mite.
·
Contamination
A disease that is transmitted through direct contact to body and body fluid called
contagious disease.
·
Epidemic- epi
-.Means- upon ,demos means = people
Wide spread occurance of
infectious disease in a community at periticular time, rapid onset ,in Large number
of popul action with in a short period of time is called Epidemic
·
.
·
Constant presence
of disease with in given geographical area called endemic .E x. Cholera
·
Pandemic
large proportion of population affected such as nation ,world
.ex.Influenzain1918.
·
Sporadic means
scattered case of infectious disease ,no connection each others ,for a long interval
.
·
Exotics a disease
which are important only in own country .ex.-Rabies in u. k.
·
An infection or infectious agent transfer from vertebral animal to man called
zoonoses .
·
Infection transmitted
from animal vertebrate to men is called antropozoonses.
·
Infection transmitted
from man to vertebrate animal called zoonatroponesex.
·
Infection found
in both men and lower vertebrate in both direction Is called amphixenoses.
·
Epidemic in
animal population called epizoonetic
·
Endemic in
animal population is called enzoonetic.
· Outbreak of disease in bird population is called epornithic.
· Infection occurance after 24 hours after of admission in a hospital is called
hospital acquired Or nosocomial infection.
·
Infection occur
during the low body immune system that organism
normally present in the Body but does not cause disease but when body immunity is
low is called opportunistic infection.
·
Adverse consequence
of a preventive diagnosis or therepeutic regiment that cause disease Called iatrogenic
disease (physician induce)
·
Quarentine-the period during which free entry to a country by
human ,animal plant or Agriculture product with significance health risk is prohibited
in order to limit the spread of Potential
infectious disease
·
Incidence-is
a health or indicator useful for taking action to control disease for research
into etiology(all new case 0f disease is called incidence)
·
Prevelance-the
term prevelance refers to all new case and all old case existing at a given
point in time ,over a period of time in a given population
·
Incidence
and prevelance are measurement of morbidity.
·
Submerged
portion of iceberg phenomena represent the hidden mass of disease.
·
Floting
tip of iceberg phenomenon represent all visible case which are seen by
physician
·
Screening-it
is a search for a disease among appearently healthy individual for prevention
of disease or the search for unrecognized disease or defect by means of rapidly
applied test, examination or other procedure in appearent healthy individuals (screening done in large
population) 3type of screening 1 mass 2 high risk 3 multiphasic screening
·
Acceptability-test should be acceptable to those person who are
involve eg. Pain full procedure ,vaginal examination.
·
Repeatability
any test which are repeat ,should
be given same result on same material or same individual that it called
reliability repeatability
·
.
·
Validity it refers to what extant the occurately measure which is purpose to
measure .it has two component 1.sensitivity 2 specificity
·
Sensitivity-it has the ability to identify currectlly all those
who have the disease that is true positive and false negative(90% have true
positive which have currectly disease,10%have false negative who does not have
disease)
·
Specificity
ability of test to identify
currectly who do not have disease is true negative means 90%non disease
case will true negative result,10%false positive means patient who do
not have disease are told they have disease
·
IMMUNITY-specific
defence of body is observe or come into observation when micro-organism enter
into the defence against these antigen inform of specific defence is called
immunity
·
Immunity
which is develops when body come in contact with infection and body give response
to against infection by developing antibody or when antigen(vaccine) are
introduced into the human body and develop antibody against vaccine is called
active immunity.
·
(when
immunity develop after infection is called active natural immunity and when
antibody develop against vaccine antigen or toxoid is called active acquired
immunity)
·
When
antibody develop by human being and animal and transferred to another to
protection against disease is called passive immunity (antibody transfer from
mother to newborn through placenta or breast milk-igA is called passive natural
immunity and if antibody or
immunoglobulin inject in human body it develop passive artificial immunity)
·
Herd
immunity –it is a level of resistance of a community or group of people to aperticular
disease.
·
Active
immunity take time to develop but it superior to passive immunity.
·
Live
vaccine made up from live attenuated bacteria it also called toxoid
·
Humoral
immunity develop by the passive immunization or injection of immunoglobulin .it
present in plasma ,it develop by activation of B-cell.
·
Cellular
immunity develop by the active infection or vaccination .it present in cellular
level develop by activation of t-cell.
·
Immunobiological
substance that protect the body against infectious disease by producing
antibody and immune mechanism is called vaccine .it two type live and killed.
·
Immunization
normaly achived by single dose of live vaccine except polio
·
When two
live vaccine required to administered should take gap at least 3 week and
different site
·
Pertusis
vaccine contraindicated in neurological disorder like seizure , epilepsy.
·
Cold chain
is a system of storage and transport of vaccine at law temperature from
manufacturing to the actual site.
·
Vaccine
which must be stored in freezer is like polio,measles and BCG.but never be
allowed to freezed.
·
BCG
vaccine should be use with in 3 hours after open and during this time place in
2to8 degree temperature and measles vaccine use with in one hour after dilution.
·
Normal
saline used as a dilution for the BCG vaccine and sterile water use in
measles(in measles stabilizer sorbitol is used)
·
In DPT
vaccine aluminium hydroxide or aluminium phosphate is used as a adjuvant to
improve sensitivity of vaccine .
·
Triage
system use START means simple triage and rapid treatment.
· Temporary harding of water is due to the calcium
,megnisium ,bicarbonate ,it can be
removedby the adding lime (caHco3) and sodium bicarbonate.
· Permanat harding or water due to the calcium,megnisium
,nitrate, chloride it remove by boiling of water.
· Water purification chlorine act as a germicidal and
it use 0.5gm for 20 litter of water.
· Constitutionof ORS new by
WHO-Nacl-2.6gm,Kcl-1.5gm,trisodiumcitrate-2.9gm,glucose13.5gm,portalwater-1 lt.
· Mid arm circumference yield a relative reliable
estimation of the body muscle mass.the useof ‘shakir tap’further simplified
assessment of mid arm circumference,the
tapis shading of three colorwhic indicate diffren level of
nutrition.RED-<12.5 indicates sever malnutrition,YELLOW-12.5-13.5 indicates
mild to moderate malnutrition.,GREEN->13.5 indicates satisfavtory
malnutrition.
· Birth rate is a simplest indicator of fertility ,but
is unsatisfactory measure of fertility because the total population is not
expose to child bearing.
· GFR(general fertility rate ) is the number of live
births per 1000 women in the reproductive age group(15-45year) in a given year.
· NRR(net reproduction rate )is define as the average
number of children a women would have if she were pass through reproductive
year bearing children at the same rate as well as the women now each agegroup.
· Epidemic drops –is due to the contamination of
mustard oil with argenine oil which contain the toxicant sanguinarine .it
inhibit the pyruvic acid which accumulate in muscle leading to bilateral non
inflammatory swelling of lower limb,dyspnea,glaucoma,cardiac failure and death.
· One aganwadi worker cover 1000 population,ASHA also
on a 1000 population one.
· Subcenter cover 5000 population in general
population,and 3000 in hilly population ,primary health center cover 30000
population in general population and 20000 in hilly population,communityhealth
center cover 80000-120000 populaton.
· Three tiers system(self local government) include
–1. Panchayat at village level, 2.panchayat samity at block level 3,zila parisad at distric
level.
· Community
development block cover 100 village and 80000-120000 population,and its
incharge is BDO-OFFICER(block development officer)
· IUD –Most
cu-T 380 for10year,cu-T 200 for 4 year, NOVA –T for 5 year.
· Lng -20 is t shape IUD,release 20mg oflevonogastrel
and it has less failure rate 02% less chanceof ectopic pregnance.
· Most common complication with IUD is hemorrhage
· Most common problem with IUD is expulsion ,and most
common cause of removal of IUD is pain.
· Best
copper-t insertion time is second and third day of menses and with in
day of the beginning of mc. Period, immediate post partum insertion – during 1st
week of after delivery, or if post purperial
than 6-8 week after delivery.
· IUD not a first choise of nulliparus women,ideal
candicate for IUD is has born at least one child and history of pelvic
dialation ,has normal menstrural period .
· IUD does not protect from STD, so need to use
condom.
· Oral pill also known as combine pill,progestron
only pill,post coital pill,once a month pill,
· OCP increase
the chance of breast cancer and decrease the chance of ovarian cancer.
· Beginning of OCP 5th day of menstrual cycle followed by a break
7 day ,and it take at same time before going to bed. It contain 28 tab.(21 tab.
Hormonal pill and 7 pill iron) iron is give for decrease cancer of anemia
,intact the pituitary function and regulate menstruation.
· Hormonal –levonorgestrol 0.75 mg for emergency
contraception most common used one tab. 75mg with 72hours and 2nd
tab. after 12 hour of first tablet.
· Combine pill prevent release of ovum from ovary by
blocking GnRH .
· Progestron only pill -cervical mucus thick and
scanty ,inhibit sperm penetration ,progestron also inhibit tubal motility delay
transport of sperm to the uterine cavity.
· Oral pill is contraindicated in such condition
as-ca breast ,liver disease, history of hyperlipidemia ,cardiac abnormality.
· Depot medroxy progesterone acetate(DMPA) and
norethistrone acetate NET-EN) are the example of injectable hormone device.
· Perkail sign
mucus plug formation after ovulation
· Spinnbarkeit means evaluation of the elasticity of
cervicalmucus used to determine time of ovulation.(esic-2016)
· Sub-dermal implant (implanone) decrease the risk of
osteoporosis women
· Health survey and development committee give by
bhore committee in1946 by sir jocef
bhore.
· Health survey and planning committee give by
mudaliar committee in1962.
· Malaria eredication program given by chadda
committee in 1963.
· Multipurpose health worker scheme given by kartar
singh committee in 1973.
· Noise is measure in decibel ,recommended maximum
noise level is 85 decibels
· Central Registration
of death and birth act 1969 become effective in april 1970,accornding to act
birth should be registered with in 14 day and death should be register with in
7 day
· Census is every 10 year first regular census taken
in india 1881.latest in 2011.
· In 2005 program launched –RCH ii launched,janani
suraksha yojana, national rural heath mission started.
· Main objective of janani surakhsha yojana(12 april
2005) is to reduce infant mortality rate and maternal mortality rate and to
increase the number of institutional
delivery.
· Vital monitoring step for infant is
RPT(RESPIRATION,PULSE TEMPRATURE)
· SOME OCCUPATIONAL DISEASE
· Coal dust cause anthrecosis
· Silica dust silicosis
· Iron dust siderosis
· Asbestos
cause fibrus lung called pneumoconiosis ,asbestosis.
· Tobacco dust cause tobacosis
· Cotton dust cause byssinosis
· Sugar cane dust cause baggassosis
· Grain dust
cause farmer lung
· Welder flash due to u,v radiation
· Heat stoke, heat cramp burn due to excessive heat
· Cold cause trench foot ,frost bite ,chilblains
· Incineration is a best method of choice for most biological waste
· Chemical disinfectant use for mainly for liquid
waste like blood ,urine ,stool etc.
· Dry thermal treatment use mainly for anatomical
waste and non infectious sharp
· Label and symbol for biological and cytotoxic
hazard
· In 2006 following program launched-
-RNCTP cover whole country since march 2006
-national family health survey 3rd conducted
-ban on child labour
-IMNCI was launched in 16 state
- · Indian
public health standered for PHC and SUB CENTER
formulated in 2007.
- · In
2008 non-communicable disease programme as pilot project launched on 4th
jan.
- · DALY
disability adjustment life year ,it measure of burden of disease and effectiveness of intervention .it
expresses year of life lost to premature death and year lived with disability Adjusted
for severity of disability.
- · HALE
is health adjusted life expectancy
- · Success
of DOTS(direct observe treatment shorter )
- -political commitment
- -good duality sputum microscopy
- -direct observe treatment
- -uninterrupted supply of good quality
drug
- -accountability
· Pulse
polio immunization programme run for 3 day first day booth coverage is
done and second and third day door to door
visit is done is called mouping up stretege.
· For
the prevention of vitamin A deficiency 1
lakh IU of vitamin A is given at 9 month and then 2 lakh IU after
every six month of interval.
· Measles
patient have vitamin-A deficiency so vitamin a supplement is given
· BCG
vaccine given at birth 0.05 ml and at 6week give 0.1ml ID , standered size –left upper arm middle of deltoid( wheel 5mm
induration read after 48 to 72 hours ,papule at 2 to 3 week ,4 to 5 week after
papule grow and break and covered with crust .,scar at 8 to 12 week.
· Bcg ,opv ,yellow fever, typhoid, cholera ,rubella
,measles, encephalitis is a live vaccine.(BOY Love The CRIME)
· expanded immunization
program launched by WHO IN 1974(EPI) ,in 1978 in india epi for six
killer disease ,in 1985-universal
immunization programme launched ,in
1995 pulse polio immunization programme launched.
· EPI
include –DPT,BCG,OPV,MEASLES. - IN 1995-PPI,HEP.B added in jan.2002
· Polio
free declared by WHO on 27 march 2014.
· World
polio day 24th oct.
· World
t.b. day 24th march
· World health day
7th april
· Dpt
,hib and hep.B and opv give at 6,10,14 week,measles and vitamin A given at 9
month and mmr at 15-18 month,5to 6year DT ,10year –TT,16 year-TT
· Know
a day injectable polio vaccine also start to give in
fractional dose two time first at 6 week
and second on 14 week.Route is intradermal and 0.1ml,before it was given 0.5ml
by SC/IM ROUTE.
· VACCINE
damaged by freezing- DPT,DT,TT,HEP.B
· Vaccine
that can be frozen with out harm-opv,measles MMR ,BCG before constitution.
· Unicef
introduce a primary healthcare concept
in 1982 is known as GOBI-3FS
-G-Growth monitoring to assess child development
-O- ORAL dehydration solution
-B- BREAST FEEDING
-I- IMMUNIZATION
-F-FOOD SUPPLIMENT FOR PREGNAT WOMEN
-F-FAMILY PLANNIG
-F-FEMALE LITRACY
- · HOLDER
method -65 degree c for30 minute and immediate cooling to 5degree
- · HTST(HIGH
TEMPRATURE SHORT TIME)-72 degree C FOR 15 second and cooled at 4 degree C
- · Rice
water stool is an important clinical
manifestation of cholera caused by vibriocholera. Hanging drop stool test done
ant its drug of choice is doxicyclin for adult and cotrimoxazole for the
children and flurazolidone for pregnant women.
- · Rabies
also known as hydrophobia, it transfer from dog bite.causative agent lyssa
virus.
- · Tetanus
is charecterised by muscle rigidity, facial muscle rigidity called risus
sardoricus,back muscle rigidity called oppisthotonic posture,it cause by
clostridium tetani.it secreate exotoxin known as tetanospasmin affect nervous system.
- · Tetanus
is one disease in which herd immunity does not protect the individual.
- · Leprosy
is caused by mycobacterium lepry ,it also known as hensen’s disease ,touch is
first sensation which loss ,drug of choice
is DAPSON.
- · TRACHOMA
–chronic infectious disease of conjectivitis and cornea causative agent
Chlamydia trachomaties,for trachoma control programme 1963 use SAFE
strategy(S-SURGERY,A-ANTIBIOTIC,F-FACIAL CLEANING,E-ENVIONMENTAL MODIFICATION)
- · Malaria is a protozoal disease transmitted by female anephelus mosquito,
fever have three stage cold,hot and sweating
- · Typhoid
–step ladder fever and rose like spot in abdomen ,it is cause by salmonella
typhi . typhi dot test and widal test is
done for 0:H antigen titer
- · Measles
is a more contagious air born disease
,cause by paramyxo virus , koplic spot
seen in mouth near lower molar teath, also show 3C SIGN( cough , coryza and conjectivitis)
- · In
measles first symptom is fever it occure at 10th day and 0n 14 day rash appear first on ear, isolation
for the maximum 7 day need
- · Dengue
is caused by aerbo virus and transmitted
by mosquito aedes agypti(aedes agypti also transmit the chikungunia and yellow
fever) it show herman sign ,raddle back fever.(3 day fever and 3day normal)
incubatin period 3 to 10 day
- · For
the detection and investigation of malaria take blood slides (thin and thick)
and geimsa stain is done.
- · Polio
is cause by picorna virus incubation period 7 to 14 day,it affect nervous
system and lower limb,decending flaccid paralysis, transmitted through
feco-oral route.only 1% patient affected with paralytic polio.
- · Culex
tritaniorrhynchus is moisquito transmit the
japanies encephalitis
- · Lymphatic
filariasis is cause by wucheria borcropti, transmite through culex mosquito it
is only single disease sample taken in night time.because its agent in day in
lymph and in night in blood plasma(biological clock), in this person look like
elephant like leg and chyluria milky color
urine is indicator of filariasis.
- · ChiCken
pox caused by vericela zoster virus and also known as human alpha virus -3,IP-14
TO 16 DAY ,first rash in trunk, centripetal and pleomorphism.
- · Rubella(german
measles) also known as 3rd day disease cause by togavirus.in this
lymph adenopathy is occure affect post
auricular and post cervical lymph node.
- · In
rubella first rash appear at face
- · In
mums period of maximum infectivity is just before &at onset of parotid
gland swealing,once the swealing of gland subside case may reguard as no large
infection.
- · For
the swine flue H1N1 need isolation and
n95 mask wear by patient and staff.isolate the patient for 7 day after onset of
symptom or 24hours after resolution of fever and respiratory symptom.
- · Diphtheria
is cause by cornibacterium diptheriae ,IP is 2 to 6 day, submendibular gland
swealling give bullneck appearance,
croup like cough is also seen.
- · Whooping
cough(pertusis) 100 day cough disease , hight pich inspiration like whoop
,hacking night cough.
- · Subcenter
level use drug kit A and B
- · At
PHC level use PHC equipment kit
- · At
CHC level use equipment kit –E TO kit-B
-
· HEATH PROGRAM IN INDIA
· National malaria contrOl programme
1953,during first five year plan
· National malaria erredication programme 1958
· National filarial control programme1955
· National leprosy control programme 1955 only dapson therepy
· National leprosy erredication programme 1983
· National world leprosy day 30 january (nearest Sunday)
· National tuberculosis programme 1962
· Revise national tuberculosis control program 1992 (sputum microscopy and
DOTS)
· DOTS PLUS MDR 1997
· National aids control program 1987
· First case of HIV dected on 1986(tamilnadu)in india
· National aids control policy
· NACO branded the STI/RTI service as surksha clinic.
· Red ribbon express project (2007-2009),world health day on 1st December.
· National program for control of blindness (1976-100%centrally
sponsored reject with trachoma control programs started in 1968)
· World sighy day 13 oct 2016
· Iodine deficiency disorder program 1962.
· Idd(iodin deficiency day) day 21 oct
· Universal immunizations program
1985.
· Pulse polio immunizations program launched in 1995.
· WHO,launched EPI in 1974,in india
EPI 1978
· National rural health mission started on 5th april 2005 for 7year
(2005-2012) to improve health care
delivery system. 1ASHA(accredited social health activist)
· Reproductive & child health program (RcH) 1997include
Ø family planning
Ø Child servival and safe motherhood 1992
Ø Client approach to health care
Ø Prevention and management of std
Ø Diarrhoeal control-zink to be use as adjuct to ORS.
Ø Pneumonia – cotri -moxazole
Ø Vitamin-A first dose 1 lakh unit,2nd dose 2 lakh unit
Ø Prevation and control of anemia - 6 month to 5 year.iron in liquid form 20 mg
elimentory iron ,100 meq. folic acid/day for 100 day,6 year to 10 year-30mg
elimentory iron,250meq.folic acid for100day
· RCH 2ND phase 1 april 2005
· Janani surksha yojana launched 12
april2005
· National mental health programme 1982
· Special nutrition program 1970 for
year child below 5year pregnant mother ,
nursing morther, supply food
300kcl,and10-12 gm protein/day,beneficieries women 500 kcl,25gm protein.
· Icds programme 1975
· Mid day meal programme 1961
· Balwadi programme 1970
· Prevention of food adultration 1954
· Consumer protection act 1954
· arthotolidin test to check accuracy and speed of water develop in 1918,0.1
ml reagent and 1 ml water (yellow color produce)
· Some disease and their incubation period
Ø 1.Chicken
pox (14-16 days)
Ø 2.Measles
10- 14 day
Ø 3.Rubella
14-21 day
Ø 4.Mumps
14- 21 day
Ø 5.Influnza
18 -72 hours
Ø 6.Syphillis
9- 90day
Ø 7.Cholera
hours to 5 day
Ø 8.Typhoid
10 -14 day
Ø 9.Rabies
3- 8 weeks
Ø 10.JE--
5-15day
Ø 11.Diptheria
2- 6day
Ø 12.Whoping
Cough- 7- 14 day
Ø 13.TB
3- 6 weeks
Ø 14.Polio-
7-14day
Ø 15.SARS-
3- 5day
Ø 16.Meningococal
meningitis 3- 4day
Ø 17.Trachoma
5-12day
Ø 18.Tetanus
6- 10 day
Ø 19.HIV
months to 10 years
Ø 20.
Staphylococcal food poisoning-- 1- 6 hrs
Ø 21.Ascriasis---
about two months
Ø 22.Hook
worm 5weeks to 9 months
Ø 21.Filariasis
8- 16 months
Ø 22.Leprosy-----
3- 5yearsñ
Ø 23.Hydated
diseases-- months to years variable
Ø 24.Malaria
Vivex 8-17 day
Ø 25.
Falciparum - 9-14 day
Ø 26.Scabies
---3- 6 weeks
Ø 27.Kalazar---
1- 4months