"Compared to other developed nations, Japan's rate of inoculation is still low."
- "Compared to other developed nations, Japan's rate of inoculation is still low."
"compared to ~" 「に比べて」
"other developed nations" 「他の先進国」
"Japan's rate of inoculation" 「日本のワクチンの接種率」
"rate of inoculation" 「ワクチンの接種率」"rate of vaccination" も使えます。
"still low" 「まだ低い」