Here are some terms you may find used in the Japanese press regarding the Corona Virus COVID-19 and their English translations. These are unofficial translations.
I got a lot of these translations from the classic WWWJDIC.
For more information on the COVID-19 situation in Japan, see this Reddit r/JapanTravel thread.
Wash your hands.
新型コロナウイルス / shingata corona uirusu / Corona Virus
感染者 / kansensha / an infected person
感染者数 / kansenshasuu / number of infected people
感染する/ kansensuru / to infect (to spread a disease)
2時感染者 / nijikansensha / secondary infection (if infected are put into a hospital and infect someone who was not infected)
接触感染 / sesshoku kansen / infection through contact
飛沫感染 / himatsu kansen / infection from droplets
感染爆発 / kansenbakuhatsu / explosive increase in infections
ソーシャルディスタンス / sousharu disutansu /social distance
一定距離 / ittei kyori / fixed distance (from something, used in context of social distancing
軽傷者 / keishousha / an infected person with light symptoms
疫病 / ekibyou / pandemic
世界的大流行 / sekaiteki dairyuukou / pandemic
防疫 / boueki / communicable disease control (e.g. by quarantine, disinfection, etc.);
休校 / kyuukou / school cancelation
延期 / enki / postponed
無期延期 / mukienki / postponed without set date to be rescheduled
中止 / chuushi / cancelled
休業 / kyuugyou / business temporarily closed
休業要請 / kyuugyou yousei / request (by the government) to temporarily closes business
休園 / kyuuen / park temporarily closed
休演 / kyuuen / performance or show canceled
時短 / jitan / reduced hours
拡大防止 / kakudai boushi / prevent from spreading further
自宅待機 / jitaku taiki / stay (quarantined) in your home
コロナ感染防止対策 / korona kansen boushi taisaku / measures to prevent the spread of the Corona Virus
臨時休館 / rinjikyuukan / a temporary (irregular) closing
時間短縮 / jikan tanshuku / reduced hours (of operation)
感染情報 / kansen jyouhou / information about the status of the infection
感染症 / kansenshou / infectious disease; infection;
感染力 / kansenryoku / degree of infectiousness (how infectious something is)
家庭感染 / katei kansen / infection at home among one’s family
蔓延 / manen / infestation; proliferation; being widespread
致死率 / chishiritsu / fatality rate
死亡率 / shibouritsu / death rate
陰性 / insei / negative
陽性 / yousei / positive
再陽性 / saiyousei / reinfection (recovered but tested positive again)
緊急事態宣言/ kinkyuu jitai senngenn / declare a state of emergency
緊急対策 / kinkyutaisaku / emergency measures
デマ情報 / dema jyouhou / fake news
消毒 / shoudoku / disinfectant
除菌 / jyokin / disinfection; sterilize;
アルコール消毒 / arukouru shoudoku / alcohol disinfectant
在庫 / zaiko / inventory
品切れ / hingire / out of stock, stock shortage
転売 / tenbai / reselling (e.g., 転売禁止 in regards to masks)
感染確認 / kansen kakunin / confirmed infections
厚生労働省 / kouseiroudoushou / Ministry of Health Labor and Welfare
高熱 / kounetsu / high fever
発熱 / hatsunetsu / to have (get) a fever
頭痛 / zutsuu / headache
検温 / kenon / temperature measurement
肺炎 / haien / pneumonia
検査 / kensa / inspection; examination;
入国規制 / nyuukoku kisei / immigration restriction
入国拒否 / nyuukokukyohi / denying entry to a country (immigration denial)
渡航制限 / tokou seigen / restrictions and limitations on flights
無観客 / mukankyaku / an event with no audience (many live events are being changed to live events with no live audience, i.e., televised only)
外出制限 / gaishutsu seigen / restrictions on going outside of your home (lockdown)
外出禁止 / gaishutsu kinshi / prohibited to go outdoors
自宅待機要請 / jitaku taiki yousei / a request to stay-at-home
不要不急 / fuyoufukyuu / unnecessary and not urgent (不要不急な渡航 travel that is neither necessary nor urgent)
指数関数的に増加する / shisuukannsuuteki ni zoukasuru / grow exponentially
密閉 密集 密接 / mippei misshuu missetsu / places with bad circulation, crowded places, close contact with others
行動変容 / koudou henyou / behavior change (change daily patterns to prevent spread)
最多を更新 / saita wo koushin / more than the previous maximum (used when reporting daily infection numbers)
医療崩壊 / iryou houkai / collapse of the healthcare system
封鎖解除 / fuusa kaijyo / “release of lockdown” city lockdown removed
警戒感 / keikaikan / feeling of urgency
個人防御服 / kojinbougyofuku / personal protective equipment
病床数 / byoushousuu / number of hospital beds
第二波 / dainiha / second wave
ガス抜き / gasu nuki / “out of gas” referring to people who are tired of doing self-restraint and start going out again.
出口戦略 / deguchi senryaku / exit strategy
新たな生活様式 / aratana seikatsu youshiki / new lifestyle
コロナ太り / korona butori / weight gained because you stayed indoors so long doing nothing during the corona pandemic